~ubuntu-branches/ubuntu/wily/u1db-qt/wily

A Database is very simple to create. It only needs an id and a path where the file will be created. A Database is a model, which can be used by elements, such as the ListView further in this example.

U1db.Database {

id: aDatabase

path: "aDatabase4"

}

U1db.Database {

id: aDatabase

path: "aDatabase4"

}

/*!

A Document can be declared at runtime. It requires at the very least a unique 'docId', but that alone won't do anything special. The snipet below snippet demonstrates the basic requirements.

In addition to this, this example displays text from the database for a specific docId and id key in a text area called 'documentContent. To update the text area at startup with either the default value or a value from the database the onCompleted function is utilized, which is also demonstrated below.

U1db.Document {

id: aDocument

database: aDatabase

docId: 'helloworld'

create: true

defaults: { "helloworld":"Hello World" }

Component.onCompleted: {

documentContent.text = aDocument.contents.helloworld

}

U1db.Document {

id: aDocument

database: aDatabase

docId: 'helloworld'

create: true

defaults: { "helloworld":"Hello World" }

Component.onCompleted: {

documentContent.text = aDocument.contents.helloworld

}

/*!

It should be possible to use a document without a database, as demonstrated in this snippet. Additionally this document will use the concept of sub-keys, as exemplified by the "bookmarks" id key + contents. This example will attempt to use the bookmark document to store docId values from the database, which will be displayed in a ListView on the second tab of the application. The user will be able to select a value from the ListView and the first tab will be modified accordingly.

U1db.Document {

id: aBookmarkDocument

docId: 'bookmarks'

create: true

defaults: { "bookmarks": [{}] }

}

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U1db.Document {

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id: aBookmarkDocument

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docId: 'bookmarks'

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create: true

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defaults: { "bookmarks": [{}] }

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}

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function switchToPreviousDocument(documentObject){

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aDocument.docId = getPreviousDocumentId(documentObject)

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}

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function switchToNextDocument(){

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aDocument.docId = getNextDocumentId(aDocument)

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}

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function getPreviousDocumentId(documentObject){

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if(typeof documentObject!='undefined'){

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/*!

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The listDocs method retrieves all the docId values from the current database. In this demonstration the values are put into an array, which is then checked to locate the docId for the current and previous documents within the database.

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var documentIds = {}

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documentIds = documentObject.database.listDocs()

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for(var i = 0; i < documentIds.length; i++){

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if(documentIds[i]===documentObject.docId && i > 0){

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return documentIds[i-1]

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}

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else if(documentIds[i]===documentObject.docId && i==0){

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return documentIds[documentIds.length-1]

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}

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}

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var documentIds = {}

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documentIds = documentObject.database.listDocs()

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for(var i = 0; i < documentIds.length; i++){

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if(documentIds[i]===documentObject.docId && i > 0){

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return documentIds[i-1]

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}

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else if(documentIds[i]===documentObject.docId && i==0){

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return documentIds[documentIds.length-1]

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}

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}

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return documentIds[0]

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}

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else{

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print("Error!")

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return ''

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}

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}

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function getNextDocumentId(documentObject){

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if(typeof documentObject!='undefined'){

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var documentIds = documentObject.database.listDocs()

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for(var i = 0; i < documentIds.length; i++){

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if(documentIds[i]===documentObject.docId && i < (documentIds.length-1)){

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return documentIds[i+1]

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}

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else if(documentIds[i]===documentObject.docId && i==(documentIds.length-1)){

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return documentIds[0]

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}

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}

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return documentIds[0]

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}

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else{

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print("Error!")

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return ''

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}

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}

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function getCurrentDocumentKey(contentsObject){

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if(typeof contentsObject!='undefined'){

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var keys = Object.keys(contentsObject);

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return keys[0]

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}

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else{

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return ''

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}

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}

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function updateContentWindow(documentText, addressBarText) {

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// Somewhere below need to check for things like invalid docId

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if(documentText!==addressBarText) {

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/*!

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These steps demonstrate the creation of a temporary document, based on a copy of the global document. This will then be used to determine if there is already a document in the database with the same docId as the address bar, and additionally with a key id with the same name.

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var tempDocument = {}

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var tempFieldName = addressBarText;

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var tempContents = {};

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tempDocument = aDocument

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tempDocument.docId = addressBarText;

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tempContents = tempDocument.contents

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NOTE: For simplicity sake this example sometimes uses the same value for both the docId and the key id, as seen here. Real life implimentations can and will differ, and this will be demonstrated elsewhere in the example code.

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var tempDocument = {}

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var tempFieldName = addressBarText;

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var tempContents = {};

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tempDocument = aDocument

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tempDocument.docId = addressBarText;

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tempContents = tempDocument.contents

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if(typeof tempContents !='undefined' && typeof tempContents[tempFieldName]!='undefined') {

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aDocument = tempDocument

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documentContent.text = tempContents[tempFieldName]

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}

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else {

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/*!

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Here the contents of the temporary document are modified, which then replaces the global document.

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documentContent.text = 'More Hello World...';

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tempContents = {}

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tempContents[tempFieldName] = documentContent.text

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tempDocument.contents = tempContents

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aDocument = tempDocument

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documentContent.text = 'More Hello World...';

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tempContents = {}

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tempContents[tempFieldName] = documentContent.text

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tempDocument.contents = tempContents

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aDocument = tempDocument

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}

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}

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else {

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/*!

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In this instance the current document's content is updated from the text view. The unique key and docId are not modified because the database already contains a record with those properties.

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tempContents = {}

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tempFieldName = getCurrentDocumentKey(aDocument.contents)

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tempContents[tempFieldName] = documentContent.text

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aDocument.contents = tempContents

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tempContents = {}

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tempFieldName = getCurrentDocumentKey(aDocument.contents)

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tempContents[tempFieldName] = documentContent.text

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aDocument.contents = tempContents

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}

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}

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Tabs {

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id: tabs

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Tab {

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title: i18n.tr("Hello U1Db!")

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page: Page {

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id: helloPage

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/*! Here a rectangle is defined that represents the lower portion of our application. It will contain all the main parts of the application.

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Rectangle {

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width: units.gu(45)

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height: units.gu(70)

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anchors.bottom: parent.bottom

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color: "#00FFFFFF"

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// The remainder of the main part of the application goes here ...

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}

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Rectangle {

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width: units.gu(45)

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height: units.gu(70)

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anchors.fill: parent

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color: "#00FFFFFF"

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Rectangle {

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width: units.gu(45)

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height: units.gu(60)

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anchors.bottom: parent.bottom

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/*!

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The following TextArea is for displaying contents for the current state of the global document, as defined by the key / name in the address bar.

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TextArea{

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id: documentContent

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selectByMouse : false

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x: units.gu(1)

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y: units.gu(1)

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width: units.gu(43)

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height: units.gu(58)

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color: "#000000"

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}

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TextArea {

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id: documentContent

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selectByMouse : false

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x: units.gu(1)

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y: units.gu(1)

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width: units.gu(43)

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height: units.gu(58)

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color: "#000000"

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}

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}

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// This rectangle contains the navigation controls

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Rectangle {

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width: units.gu(43)

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height: units.gu(5)

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anchors.top: addressBarArea.bottom

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x: units.gu(1.5)

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color: "#00FFFFFF"

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Row {

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width: units.gu(43)

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height: units.gu(5)

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anchors.verticalCenter: parent.verticalCenter

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spacing: units.gu(2)

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Button {

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text: "<"

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onClicked: updateContentWindow(switchToPreviousDocument(aDocument), addressBar.text)

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}

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Button {

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text: "Home"

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onClicked: updateContentWindow(getCurrentDocumentKey(aDocument.contents),'helloworld')

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}

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Button {

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text: "Save"

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onClicked: updateContentWindow(getCurrentDocumentKey(aDocument.contents),addressBar.text)

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}

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Button {

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text: ">"

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onClicked: updateContentWindow(switchToNextDocument(aDocument), addressBar.text)

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}

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}

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}

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Rectangle {

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id: addressBarArea

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width: units.gu(45)

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height: units.gu(5)

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anchors.top: parent.top

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TextField {

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id: addressBar

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width: units.gu(43)

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anchors.verticalCenter: parent.verticalCenter

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x: units.gu(1)

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hasClearButton: false

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/*!

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There is an object within in the 'aDocument' model defined earlier called 'contents', which contains a key called 'hello', which represents a search string. In this example the key will represent the name of a document in the database, which will be displayed in the address bar. Displaying the key is demonstrated here:

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text: displayKey(aDocument.contents)

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function displayKey(documentObject){

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var keys = Object.keys(documentObject);

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return keys[0]

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}

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text: getCurrentDocumentKey(aDocument.contents)

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onAccepted: {

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onClicked: updateContentWindow(getCurrentDocumentKey(aDocument.contents),addressBar.text)

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}

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}

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}

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}

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}

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}

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Tab {

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title: i18n.tr("Bookmarks")

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page: Page {

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id: bookmarkPage

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Label {

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text: aDocument.contents.helloworld

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}

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}

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}

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}

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}

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