如何检索视图的维度?

我有一个由tableelayout, TableRow和TextView组成的视图。我想让它看起来像一个网格。我需要得到这个网格的高度和宽度。方法getHeight()和getWidth()总是返回0。当我动态格式化网格和使用XML版本时，就会发生这种情况。

如何检索视图的维度?

下面是我在调试中用来检查结果的测试程序:

import android.app.Activity;
import android.os.Bundle;
import android.widget.TableLayout;
import android.widget.TextView;

public class appwig extends Activity {  
    @Override
    public void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
      setContentView(R.layout.maindemo);  //<- includes the grid called "board"
      int vh = 0;   
      int vw = 0;

      //Test-1 used the xml layout (which is displayed on the screen):
      TableLayout tl = (TableLayout) findViewById(R.id.board);  
      tl = (TableLayout) findViewById(R.id.board);
      vh = tl.getHeight();     //<- getHeight returned 0, Why?  
      vw = tl.getWidth();     //<- getWidth returned 0, Why?   

      //Test-2 used a simple dynamically generated view:        
      TextView tv = new TextView(this);
      tv.setHeight(20);
      tv.setWidth(20);
      vh = tv.getHeight();    //<- getHeight returned 0, Why?       
      vw = tv.getWidth();    //<- getWidth returned 0, Why?

    } //eof method
} //eof class

当前回答

你可以使用OnResume()中调用的广播

例如:

int vh = 0;   
int vw = 0;

public void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
      setContentView(R.layout.maindemo);  //<- includes the grid called "board"

      registerReceiver(new BroadcastReceiver() {
            @Override
            public void onReceive(Context context, Intent intent) {
                TableLayout tl = (TableLayout) findViewById(R.id.board);  
                tl = (TableLayout) findViewById(R.id.board);
                vh = tl.getHeight();       
                vw = tl.getWidth();               
            }
      }, new IntentFilter("Test"));
}

protected void onResume() {
        super.onResume();

        Intent it = new Intent("Test");
        sendBroadcast(it);

}

你不能在OnCreate ()， onStart()，甚至在onResume()中获得视图的高度，原因是kcoppock响应

2017-09-25 01:56:59

其他回答

你可以使用OnResume()中调用的广播

例如:

int vh = 0;   
int vw = 0;

public void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
      setContentView(R.layout.maindemo);  //<- includes the grid called "board"

      registerReceiver(new BroadcastReceiver() {
            @Override
            public void onReceive(Context context, Intent intent) {
                TableLayout tl = (TableLayout) findViewById(R.id.board);  
                tl = (TableLayout) findViewById(R.id.board);
                vh = tl.getHeight();       
                vw = tl.getWidth();               
            }
      }, new IntentFilter("Test"));
}

protected void onResume() {
        super.onResume();

        Intent it = new Intent("Test");
        sendBroadcast(it);

}

你不能在OnCreate ()， onStart()，甚至在onResume()中获得视图的高度，原因是kcoppock响应

2017-09-25 01:56:59

像这样使用视图的post方法

post(new Runnable() {   
    @Override
    public void run() {
        Log.d(TAG, "width " + MyView.this.getMeasuredWidth());
        }
    });

2011-12-06 15:20:56

你应该查看视图生命周期:http://developer.android.com/reference/android/view/View.html通常你不应该知道宽度和高度，直到你的活动进入onResume状态。

2010-11-13 22:52:05

ViewTreeObserver和onWindowFocusChanged()根本不是必要的。

如果你膨胀的TextView作为布局和/或放一些内容在它和设置LayoutParams然后你可以使用getMeasuredHeight()和getMeasuredWidth()。

BUT you have to be careful with LinearLayouts (maybe also other ViewGroups). The issue there is, that you can get the width and height after onWindowFocusChanged() but if you try to add some views in it, then you can't get that information until everything have been drawn. I was trying to add multiple TextViews to LinearLayouts to mimic a FlowLayout (wrapping style) and so couldn't use Listeners. Once the process is started, it should continue synchronously. So in such case, you might want to keep the width in a variable to use it later, as during adding views to layout, you might need it.

2012-08-20 23:04:51

更正: 我发现上面的解决方案很糟糕。尤其是当你的手机很慢的时候。在这里，我找到了另一个解决方案: 计算出元素的px值，包括边距和边距: Dp到px: https://stackoverflow.com/a/6327095/1982712

或者dimensions .xml到px: https://stackoverflow.com/a/16276351/1982712

Sp对px: https://stackoverflow.com/a/9219417/1982712(反向解决方案)

或者尺寸到px: https://stackoverflow.com/a/16276351/1982712

就是这样。

2013-08-21 03:30:04

如何检索视图的维度?

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