错误: TiExceptionHandler:消息:未捕获错误:已请求索引4，大小为4

Question

我正在尝试根据所选的图像更改显示的内容。代码是：

Ti.Database.install('data.sqlite', 'datadb');
var db = Titanium.Database.open('datadb');
var data = db.execute('select * from data');
var imageBook = [];


while(data.isValidRow()){       

 imageBook[data.fieldByName('id')]  = Ti.UI.createImageView({
image:  data.fieldByName('id')+'.png',
width:85, 
height:140
});


imageBook[data.fieldByName('id')].addEventListener('click', function(event){
 winBook.open();
   content = data.fieldByName('content');   
});


 data.next();
}

我得到的错误

[ERROR] :  TiResultSet: (KrollRuntimeThread) [131428,163249] Exception getting value for column 3: Index 4 requested, with a size of 4
[ERROR] :  TiResultSet: android.database.CursorIndexOutOfBoundsException: Index 4 requested, with a size of 4
[ERROR] :  TiResultSet:     at android.database.AbstractCursor.checkPosition(AbstractCursor.java:426)
[ERROR] :  TiResultSet:     at android.database.AbstractWindowedCursor.checkPosition(AbstractWindowedCursor.java:136)
[ERROR] :  TiResultSet:     at android.database.AbstractWindowedCursor.getType(AbstractWindowedCursor.java:130)
[ERROR] :  TiResultSet:     at android.database.AbstractWindowedCursor.isFloat(AbstractWindowedCursor.java:125)
[ERROR] :  TiResultSet:     at ti.modules.titanium.database.TiResultSetProxy.internalGetField(TiResultSetProxy.java:109)
[ERROR] :  TiResultSet:     at ti.modules.titanium.database.TiResultSetProxy.internalGetFieldByName(TiResultSetProxy.java:205)
[ERROR] :  TiResultSet:     at ti.modules.titanium.database.TiResultSetProxy.internalGetFieldByName(TiResultSetProxy.java:195)
[ERROR] :  TiResultSet:     at ti.modules.titanium.database.TiResultSetProxy.fieldByName(TiResultSetProxy.java:169)
[ERROR] :  TiResultSet:     at org.appcelerator.kroll.runtime.v8.V8Object.nativeFireEvent(Native Method)
[ERROR] :  TiResultSet:     at org.appcelerator.kroll.runtime.v8.V8Object.fireEvent(V8Object.java:64)
[ERROR] :  TiResultSet:     at org.appcelerator.kroll.KrollProxy.doFireEvent(KrollProxy.java:884)
[ERROR] :  TiResultSet:     at org.appcelerator.kroll.KrollProxy.handleMessage(KrollProxy.java:1107)
[ERROR] :  TiResultSet:     at org.appcelerator.titanium.proxy.TiViewProxy.handleMessage(TiViewProxy.java:327)
[ERROR] :  TiResultSet:     at android.os.Handler.dispatchMessage(Handler.java:98)
[ERROR] :  TiResultSet:     at android.os.Looper.loop(Looper.java:136)
[ERROR] :  TiResultSet:     at org.appcelerator.kroll.KrollRuntime$KrollRuntimeThread.run(KrollRuntime.java:112)
[WARN] :   W/System.err: android.database.CursorIndexOutOfBoundsException: Index 4 requested, with a size of 4
[WARN] :   W/System.err:    at android.database.AbstractCursor.checkPosition(AbstractCursor.java:426)
[WARN] :   W/System.err:    at android.database.AbstractWindowedCursor.checkPosition(AbstractWindowedCursor.java:136)
[WARN] :   W/System.err:    at android.database.AbstractWindowedCursor.getType(AbstractWindowedCursor.java:130)
[WARN] :   W/System.err:    at android.database.AbstractWindowedCursor.isFloat(AbstractWindowedCursor.java:125)
[WARN] :   W/System.err:    at ti.modules.titanium.database.TiResultSetProxy.internalGetField(TiResultSetProxy.java:109)
[WARN] :   W/System.err:    at ti.modules.titanium.database.TiResultSetProxy.internalGetFieldByName(TiResultSetProxy.java:205)
[WARN] :   W/System.err:    at ti.modules.titanium.database.TiResultSetProxy.internalGetFieldByName(TiResultSetProxy.java:195)
[WARN] :   W/System.err:    at ti.modules.titanium.database.TiResultSetProxy.fieldByName(TiResultSetProxy.java:169)
[WARN] :   W/System.err:    at org.appcelerator.kroll.runtime.v8.V8Object.nativeFireEvent(Native Method)
[WARN] :   W/System.err:    at org.appcelerator.kroll.runtime.v8.V8Object.fireEvent(V8Object.java:64)
[WARN] :   W/System.err:    at org.appcelerator.kroll.KrollProxy.doFireEvent(KrollProxy.java:884)
[WARN] :   W/System.err:    at org.appcelerator.kroll.KrollProxy.handleMessage(KrollProxy.java:1107)
[WARN] :   W/System.err:    at org.appcelerator.titanium.proxy.TiViewProxy.handleMessage(TiViewProxy.java:327)
[WARN] :   W/System.err:    at android.os.Handler.dispatchMessage(Handler.java:98)
[WARN] :   W/System.err:    at android.os.Looper.loop(Looper.java:136)
[WARN] :   W/System.err:    at org.appcelerator.kroll.KrollRuntime$KrollRuntimeThread.run(KrollRuntime.java:112)
[ERROR] :  TiExceptionHandler: (main) [124,163373] ----- Titanium Javascript Runtime Error -----
[ERROR] :  TiExceptionHandler: (main) [0,163373] - In app.js:768,21
[ERROR] :  TiExceptionHandler: (main) [0,163373] - Message: Uncaught Error: Index 4 requested, with a size of 4
[ERROR] :  TiExceptionHandler: (main) [1,163374] - Source:         content = data.fieldByName('content');
[ERROR] :  V8Exception: Exception occurred at app.js:768: Uncaught Error: Index 4 requested, with a size of 4

编辑:我知道错误发生的原因。eventlistener调用当前的"Data.fieldByName('content');“，当使用data.next()单击eventlistener时，它将尝试检索一个不存在的列。你知道如何解决这个问题，或者在事件侦听器创建后将"Data.fieldByName('content');“值设置为静态的吗？

Answer 1

问题是方法next (在结尾处while行不存在)，所以当您单击图像视图时，它会尝试捕捉行，但实际上没有行。

尝试创建对象：。

var bookClicked = function bookClicked (c) {
    // c => content of each image view
    winBook.open();
};

while(data.isValidRow()){
    var id = data.fieldByName('id');
    var content = data.fieldByName('content');        
    imageBook[id] = {
       "content" : content,
       "view" : Ti.UI.createImageView({
           image: data.fieldByName('id')+'.png',
           width: 85, 
           height: 140
       })
    };
    imageBook[id].view.addEventListener('click', bookClicked(imageBook[id].content));
    data.next();
}