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Android 中 LayoutParams 的用法

一个控件应当使用它的父控件的 LayoutParams 类型。因此,一个 TableVow 应该使用 TableLayout.Params 。

所以,以一个 TableRow 为例:

        TableRow tableRow = new TableRow(context);        tableRow.setLayoutParams(new TableLayout.LayoutParams(            TableLayout.LayoutParams.MATCH_PARENT,            TableLayout.LayoutParams.MATCH_PARENT,1.0f));

当我没有指明 LayoutParams 的类型时,TableRow 没有能够自动适应屏幕长度。因为 TableRow 不认识 TableLayout 的大小。所以此时即使设置了 weight 也不好使。

 

[android-developers] Re: Possible bug in TableLayout

Romain Guy Mon, 16 Feb 2009 19:57:16 -0800

Your code is *NOT* equivalent to the XML. You are using the wrongLayoutParams everywhere. A widget must have the LayoutParams of its*parent*. Therefore, the rows must have TableLayout.LayoutParams, theTextViews must have TableRow.LayoutParams and the TableLayout musthave FrameLayout.LayoutParams.
Here is your code, corrected, and it works just fine.package com.test;import android.app.Activity;import android.graphics.Color;import android.os.Bundle;import android.view.View;import android.widget.FrameLayout;import android.widget.TableLayout;import android.widget.TableRow;import android.widget.TextView;public class Test extends Activity {        /** Called when the activity is first created. */        @Override        public void onCreate(Bundle savedInstanceState) {                super.onCreate(savedInstanceState);                setContentView(buildTableViewFromSource());        }        private View buildTableViewFromSource() {                FrameLayout.LayoutParams pTable = new FrameLayout.LayoutParams(                                TableRow.LayoutParams.FILL_PARENT,                                TableRow.LayoutParams.FILL_PARENT);                TableLayout table = new TableLayout(this);                table.setBackgroundColor(Color.RED);                table.setLayoutParams(pTable);                TableRow rowTop = new TableRow(this);                TableLayout.LayoutParams pRowTop = new TableLayout.LayoutParams(                                TableLayout.LayoutParams.FILL_PARENT,                                TableLayout.LayoutParams.WRAP_CONTENT);                pRowTop.weight = 1;                rowTop.setBackgroundColor(Color.BLUE);                TextView txt = new TextView(this);                txt.setText("Top Content");                rowTop.addView(txt, new TableRow.LayoutParams(                                TableRow.LayoutParams.FILL_PARENT,                                TableRow.LayoutParams.WRAP_CONTENT));                TableRow rowBottom = new TableRow(this);                rowBottom.setBackgroundColor(Color.GREEN);                TextView txtBottom = new TextView(this);                txtBottom.setText("Bottom Content");                TableLayout.LayoutParams pRowBottom = new TableLayout.LayoutParams(                                TableLayout.LayoutParams.WRAP_CONTENT,                                TableLayout.LayoutParams.WRAP_CONTENT);                rowBottom.addView(txtBottom, new TableRow.LayoutParams(                                TableRow.LayoutParams.FILL_PARENT,                                TableRow.LayoutParams.WRAP_CONTENT));                table.addView(rowTop, pRowTop);                table.addView(rowBottom, pRowBottom);                return table;        }}