java - 将 View 添加到 Android LinearLayout

Question

我有 Vertical ScrollView，我将在单击按钮后添加一些 View 。这是 ScrollView 的 xml

<ScrollView
    android:background = "@drawable/border"
    android:layout_weight="31"
    android:id="@+id/scrollView1"
    android:layout_width="match_parent"
    android:layout_height="0dp" >

    <LinearLayout
        android:id="@+id/layoutScroll"
        android:padding = "10dp"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="vertical" >






        <LinearLayout
            android:id="@+id/layoutContainer"
            android:padding="5dp"
            android:orientation="vertical"
            android:background="@drawable/border_2"
            android:layout_width="fill_parent"
            android:layout_height = "wrap_content">

            <RelativeLayout
                android:id="@+id/relativeLayout"
                android:layout_height = "wrap_content"
                android:layout_width = "fill_parent">
                <TextView
                    android:id="@+id/textWord"
                    android:layout_width="match_parent"
                    android:layout_height="wrap_content"
                    android:text="@string/word"
                    android:textAppearance="?android:attr/textAppearanceMedium" />

                <TextView
                    android:id="@+id/textNumber"
                    android:background = "@drawable/border_1"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:layout_alignParentRight="true"
                    android:layout_alignParentTop="true"
                    android:text=" 1 "
                    android:textAppearance="?android:attr/textAppearanceMedium" />

            </RelativeLayout>

            <EditText 
                android:id="@+id/editWord"
                android:layout_marginTop="3dp"
                android:layout_gravity="left"
                android:inputType="text"
                android:textAppearance="?android:attr/textAppearanceMedium"
                android:layout_width="fill_parent"
                android:layout_height="wrap_content"
                android:lines="1"
                android:scrollbars="horizontal"/>
            <TextView 
                android:id="@+id/textDefinition"
                android:textAppearance="?android:attr/textAppearanceMedium"
                android:layout_width="fill_parent"
                android:layout_height="wrap_content"
                android:text = "@string/definition" />
            <EditText 
                android:id="@+id/editDefinition"
                android:gravity="top|left"
                android:inputType="textMultiLine"
                android:layout_width="fill_parent"
                android:layout_height="wrap_content"
                android:lines="3"
                android:maxLines="3"
                android:scrollbars="vertical"/>               
        </LinearLayout>
        <TextView
            android:id="@+id/textEmpty"
            android:layout_width="fill_parent"
            android:layout_height="wrap_content"
            android:lines="1"
            android:textAppearance="?android:attr/textAppearanceMedium" />





    </LinearLayout>
</ScrollView>

在此函数中，我创建相同的对象以将它们添加到 LinearLayout

private void initInterface (){
    layoutScroll = (LinearLayout) findViewById (R.id.layoutScroll);
    layoutContainer = new LinearLayout(getApplicationContext());
    relativeLayout = new RelativeLayout(getApplicationContext());

    textWord = new TextView(getApplicationContext());
    textDefinition= new TextView(getApplicationContext());
    textNumber = new TextView(getApplicationContext());
    textEmpty = new TextView(getApplicationContext());

    editWord = new EditText(getApplicationContext());
    editDefinition = new EditText(getApplicationContext());


    layoutContainer.setPadding(5, 5, 5, 5);
    layoutContainer.setOrientation(LinearLayout.VERTICAL);
    layoutContainer.setBackgroundResource(R.drawable.border_2);
    LinearLayout.LayoutParams param1 = 
            new LayoutParams(LayoutParams.MATCH_PARENT , LayoutParams.WRAP_CONTENT );
    layoutContainer.setLayoutParams(param1);


    RelativeLayout.LayoutParams param2 = 
            new RelativeLayout.LayoutParams (RelativeLayout.LayoutParams.MATCH_PARENT, RelativeLayout.LayoutParams.WRAP_CONTENT);
    relativeLayout.setLayoutParams(param2);
    textWord.setLayoutParams(param2);
    textWord.setTextAppearance(this,android.R.style.TextAppearance_Medium);
    textWord.setText("Word:");

    RelativeLayout.LayoutParams param3= 
            new RelativeLayout.LayoutParams 
            (RelativeLayout.LayoutParams.WRAP_CONTENT, 
                    RelativeLayout.LayoutParams.WRAP_CONTENT);
    param3.addRule(RelativeLayout.ALIGN_PARENT_TOP);
    param3.addRule(RelativeLayout.ALIGN_PARENT_RIGHT);
    textNumber.setBackgroundResource(R.drawable.border_1);
    textNumber.setTextAppearance(this,android.R.style.TextAppearance_Medium);
    textNumber.setLayoutParams(param3);

    relativeLayout.addView(textWord);
    relativeLayout.addView(textNumber);


    LinearLayout.LayoutParams param4 = param1;
    param4.setMargins(0, 3, 0, 0);
    editWord.setGravity(Gravity.LEFT);
    editWord.setTextAppearance(this,android.R.style.TextAppearance_Medium);
    editWord.setLines(1);
    editWord.setHorizontallyScrolling(true);
    editWord.setLayoutParams(param4);


    textDefinition.setLayoutParams(param1);
    textDefinition.setTextAppearance(this,android.R.style.TextAppearance_Medium);
    textDefinition.setText("Definition:");

    editDefinition.setGravity(Gravity.TOP | Gravity.LEFT);
    editDefinition.setSingleLine(false);
    editDefinition.setLayoutParams(param1);
    editDefinition.setMaxLines(3);
    editDefinition.setLines(3);
    editDefinition.setVerticalScrollBarEnabled(true);
    editDefinition.setImeOptions(EditorInfo.IME_FLAG_NO_ENTER_ACTION);

    textEmpty.setTextAppearance(this,android.R.style.TextAppearance_Medium);
    textEmpty.setLines(1);
    textEmpty.setLayoutParams(param1);

    layoutContainer.addView(relativeLayout);
    layoutContainer.addView(editWord);
    layoutContainer.addView(textDefinition);
    layoutContainer.addView(editDefinition);




}

然后我将它们添加到布局中，如下所示。

public void onCLick_Add(View v){
    layoutScroll.addView(layoutContainer);
    layoutScroll.addView(textEmpty);

}

问题是它只能工作一次。当我第二次单击该按钮时，应用程序崩溃了。预先感谢您。

Answer 1

您的日志显示:

Caused by: java.lang.IllegalStateException: The specified child already has a parent. You must call removeView() on the child's parent first.

您尝试在多次单击时多次添加相同的layoutContainer和textEmpty。这会失败，因为它们已经被添加，因此已经有一个父级。 (您不能将相同的 View 添加到多个父级)

解决方案我猜你想在每次按下按钮时创建一个新的 View 并将其添加到你的layoutScroll中。您应该为每次点击再次调用您的 init 方法:

public void onCLick_Add(View v){
  initInterface();
  layoutScroll.addView(layoutContainer);
  layoutScroll.addView(textEmpty);
}

我还建议将 initInterface() 分为:

private View createLayoutContainer();
private View createTextEmpty();

确保在外部初始化scrollView(例如onCreate)，并在createLayoutContainer() 中局部声明layoutContainer 之类的 View ，而不是全局声明。

这里是它的外观 fragment :

private View createLayoutContainer(){
  LinearLayout layoutContainer = new LinearLayout(getApplicationContext());
  RelativeLayout relativeLayout = new RelativeLayout(getApplicationContext());

  TextView textWord = new TextView(getApplicationContext());
  ...
  return layoutContainer;
}

public void onCLick_Add(View v){
  layoutScroll.addView(createLayoutContainer());
  layoutScroll.addView(createTextEmptyView());
}