嵌套的LinearLayouts無法正常工作

Question

我已經嘗試了兩天了，以創建嵌套的線性布局（線性布局內的線性布局）很少成功。 我的主布局包含3個部分，分別按權重分別為45、45和10。當我運行該布局時，它似乎工作得很好。 我在不同顏色的屏幕上得到3個矩形。

創建“子”線性布局並將其添加到母版后，子布局將主導屏幕。 子線性布局的權重為35,35和30。因此，我希望在屏幕上看到頂部矩形分成3個較細的矩形。 相反，我得到了屬於子布局的3個矩形。

有任何想法嗎？

公共無效onCreate（捆綁保存的InstanceState）{super.onCreate（savedInstanceState）;

    // Ensure there is a full screen blank window to work with
    requestWindowFeature(Window.FEATURE_NO_TITLE);
    getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
                         WindowManager.LayoutParams.FLAG_FULLSCREEN);

      testViewA = new TestView(this);
      testViewB = new TestView(this);
      testViewC = new TestView(this);

      testViewD = new TestView(this);
      testViewE = new TestView(this);
      testViewF = new TestView(this);

      testViewA.color = 0;
      testViewB.color = 1;
      testViewC.color = 2;
      testViewD.color = 3;
      testViewE.color = 4;
      testViewF.color = 5;

    LinearLayout.LayoutParams paramsA = new LinearLayout.LayoutParams(LayoutParams.FILL_PARENT, 0, .45f);
    LinearLayout.LayoutParams paramsB = new LinearLayout.LayoutParams(LayoutParams.FILL_PARENT, 0, .45f);
    LinearLayout.LayoutParams paramsC = new LinearLayout.LayoutParams(LayoutParams.FILL_PARENT, 0, .10f);

    LinearLayout.LayoutParams paramsX = new LinearLayout.LayoutParams(LayoutParams.FILL_PARENT, 0, .35f);
    LinearLayout.LayoutParams paramsY = new LinearLayout.LayoutParams(LayoutParams.FILL_PARENT, 0, .35f);
    LinearLayout.LayoutParams paramsZ = new LinearLayout.LayoutParams(LayoutParams.FILL_PARENT, 0, .30f);

    paramsA.setMargins(10, 10, 10, 10);
    paramsB.setMargins(10, 10, 10, 10);

    testViewA.setLayoutParams(paramsA);
    testViewB.setLayoutParams(paramsB);
    testViewC.setLayoutParams(paramsC);
    testViewD.setLayoutParams(paramsX);
    testViewE.setLayoutParams(paramsY);
    testViewF.setLayoutParams(paramsZ);

    LinearLayout sub1 = new LinearLayout(this);
    sub1.setOrientation(LinearLayout.VERTICAL);
    sub1.setLayoutParams(new LayoutParams(LayoutParams.FILL_PARENT, LayoutParams.FILL_PARENT));
    sub1.addView(testViewD);
    sub1.addView(testViewE);
    sub1.addView(testViewF);

    LinearLayout masterL = new LinearLayout(this);
    masterL.setOrientation(LinearLayout.VERTICAL);
    masterL.setLayoutParams(new LayoutParams(LayoutParams.FILL_PARENT, LayoutParams.FILL_PARENT));
    masterL.addView(sub1);
    masterL.addView(testViewB);
    masterL.addView(testViewC);

    setContentView(masterL);

}

Answer 1

您的布局可以正常工作，但是您paramsA為實際添加到masterL LinearLayout的新sub-layout（ sub1 ）添加LayoutParams paramsA ，而是設置了一組新的LayoutParams （ width和height設置為FILL_PARENT ？!!？）使您的sub1整個主版面。 您所要做的就是將正確的LayoutParams設置為sub1 ：

    sub1.setLayoutParams(paramsA);

注意：正如其他人所說，嵌套權重對於性能而言並不太好，也許您可​​以使用其他類型的布局來改善布局。

Answer 2

僅當將子級的布局參數設置為wrap_content並且它們中確實有額外的空格時，layout weight屬性才有用。

Answer 3

首先是在xml中執行此操作，以Java編寫時，它很難讀取/維護布局代碼（特別是當它這么簡單時）。 幾乎沒有充分的理由在Java中編寫此類屬性。

其次，不要嵌套權重，權重對性能不利： http : //developer.android.com/resources/articles/layout-tricks-efficiency.html您應該能夠提出不需要的替代布局嵌套的布局。

第三，如果您絕對必須使用嵌套權重（同樣可以肯定也不要使用嵌套權重），則需要設置sub1的權重。 通過設置其高度以填充父級而不是權重為0，就可以告訴它填充屏幕，因此它完全按照您的指示進行操作就不足為奇了。

Answer 4

你需要 ：

1）將要為其設置體重的孩子的身高設置為0 。

2）設置父級布局的setweightSum（子級權重之和）。

檢查此代碼作為我從您的代碼示例中獲得的示例：

 requestWindowFeature(Window.FEATURE_NO_TITLE);
        getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
                             WindowManager.LayoutParams.FLAG_FULLSCREEN);

          TextView TextViewA = new TextView(this);
          TextView   TextViewB = new TextView(this);
          TextView      TextViewC = new TextView(this);

          TextView      TextViewD = new TextView(this);
          TextView      TextViewE = new TextView(this);
          TextView      TextViewF = new TextView(this);

         TextViewA.setBackgroundColor( Color.RED);
          TextViewB.setBackgroundColor( Color.BLACK);
          TextViewC.setBackgroundColor( Color.BLUE);
          TextViewD.setBackgroundColor( Color.CYAN);
          TextViewE.setBackgroundColor( Color.GRAY);
          TextViewF.setBackgroundColor( Color.GREEN);



       LinearLayout.LayoutParams paramsA = new LinearLayout.LayoutParams(LayoutParams.FILL_PARENT, 0, .45f);
        LinearLayout.LayoutParams paramsB = new LinearLayout.LayoutParams( LayoutParams.FILL_PARENT,0, .45f);
        LinearLayout.LayoutParams paramsC = new LinearLayout.LayoutParams(LayoutParams.FILL_PARENT,0, .10f);

        LinearLayout.LayoutParams paramsX = new LinearLayout.LayoutParams( LayoutParams.FILL_PARENT, 0,.35f);
        LinearLayout.LayoutParams paramsY = new LinearLayout.LayoutParams( LayoutParams.FILL_PARENT,0, .35f);
        LinearLayout.LayoutParams paramsZ = new LinearLayout.LayoutParams( LayoutParams.FILL_PARENT,0, .30f);

        paramsA.setMargins(10, 10, 10, 10);
       paramsB.setMargins(10, 10, 10, 10);

      TextViewA.setLayoutParams(paramsA);
        TextViewB.setLayoutParams(paramsB);
        TextViewC.setLayoutParams(paramsC);
        TextViewD.setLayoutParams(paramsX);
        TextViewE.setLayoutParams(paramsY);
        TextViewF.setLayoutParams(paramsZ);

        LinearLayout sub1 = new LinearLayout(this);
        sub1.setOrientation(LinearLayout.VERTICAL);

        sub1.setLayoutParams(new LayoutParams( LayoutParams.FILL_PARENT,0,0.45f));
        sub1.setWeightSum(1f);
        sub1.addView(TextViewD);
        sub1.addView(TextViewE);
        sub1.addView(TextViewF);

        LinearLayout masterL = new LinearLayout(this);
        masterL.setOrientation(LinearLayout.VERTICAL);
        masterL.setLayoutParams(new LayoutParams(LayoutParams.FILL_PARENT, LayoutParams.FILL_PARENT));
       masterL.setWeightSum(1f);
        masterL.addView(sub1);
        masterL.addView(TextViewB);
        masterL.addView(TextViewC);

        setContentView(masterL);