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此問題與我之前發佈的問題有關。 Views removed using removeView() are there when I next open the Activity (Android)getChildCount（）在TableLayout上調用時返回0
背景：當用戶登錄到我的應用程序中時，它們將從登錄活動中移至主頁面活動。主頁有一個包含動態生成按鈕的TableLayout。但是，如果用戶註銷並重新登錄，所有這些按鈕都會重複出現，因此我試圖找出如何在生成這些按鈕後最好地移除這些按鈕。在我之前的文章中，有人建議我在主頁面活動開始時刪除按鈕，然後再繪製新的按鈕，所以這就是我想要實現的。
但是，當我在此佈局上調用getChildCount（）時，它並不總是返回正確的答案。
到目前爲止，這裏是在主頁活動開始運行代碼：
TableLayout tableLayout = (TableLayout)findViewById(R.id.MainPageTableTitle);
//removeSectionButtons(tableLayout); this is where i am trying to remove the buttons
System.out.println("there are oncreate " + tableLayout.getChildCount());
drawButtons(tableLayout);
System.out.println("there are ondraw " + tableLayout.getChildCount());
打印的第一行返回0，第二個打印行總是返回正確答案（按鈕的數量包括所有重複的）。但我不確定爲什麼getChildCount（）第一次返回錯誤的答案。如果任何人都可以解釋我是令人難以置信的感激
我drawButtons（）方法如下（它吸引每行有兩個按鈕）：
public void drawButtons(TableLayout tableLayout){
//get the number of buttons
int noOfButtons = mySectionTableHandler.getSectionDetails().size();
//calculate the number of rows needed (there are 2 columns)
//set flag to say if buttons are odd as it affects how many are drawn
int noOfRows;
boolean evenNoOfButtons;
if(noOfButtons % 2 == 0){
//even no of buttons
noOfRows = noOfButtons/2;
evenNoOfButtons = true;
} else {
//odd no of buttons
noOfRows = (noOfButtons+1)/2;
evenNoOfButtons = false;
}
//counter to give each button a unique id
int counter = 1;
for(int i = 0; i<noOfRows;i++){
TableRow newRow = new TableRow(this);
Button a = new Button(MainPageActivity.this);
a.setId(counter);
sectionButtons.put(counter, a);
counter++;
newRow.addView(a);
//if there are even buttons OR if there are an odd no
//of buttons but this isn't the last row then add
//second button to row
if(evenNoOfButtons || (!evenNoOfButtons && (noOfRows-1!=i))){
Button b = new Button(MainPageActivity.this);
b.setId(counter);
sectionButtons.put(counter, b);
counter++;
newRow.addView(b);
}
tableLayout.addView(newRow);
}
}