Android之activity中新建控件
了解了5大布局,我们会发现这些布局都是静态的,如何让系统自动生成控件呢?这就需要activity来帮忙了
今天我们讲的就是用activity新建布局
用案例来说吧!
实现一个输入行和列自动生成表格并生成背景颜色
效果如图
代码如下:
<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent" android:orientation="vertical" > <LinearLayout android:layout_width="match_parent" android:layout_height="wrap_content" android:orientation="vertical" > <EditText android:id="@+id/text_row" android:layout_width="match_parent" android:layout_height="wrap_content" android:layout_gravity="left|top" android:ems="10" android:hint="@string/text_row" android:inputType="number"> <requestFocus /> </EditText> <EditText android:id="@+id/text_column" android:layout_width="match_parent" android:layout_height="wrap_content" android:layout_gravity="left|top" android:ems="10" android:hint="@string/text_column" android:inputType="number" /> <Button android:id="@+id/btn_commit" android:layout_width="match_parent" android:layout_height="wrap_content" android:layout_gravity="center_vertical|center_horizontal" android:text="@string/btn_commit" /> </LinearLayout> <TableLayout android:layout_weight="1" android:id="@+id/tablelayout" android:layout_width="match_parent" android:layout_height="wrap_content" > </TableLayout> </LinearLayout>
1 package com.example.linearlayout; 2 3 import android.app.Activity; 4 import android.graphics.Color; 5 import android.os.Bundle; 6 import android.view.Menu; 7 import android.view.MenuItem; 8 import android.view.View; 9 import android.view.View.OnClickListener; 10 import android.widget.Button; 11 import android.widget.LinearLayout; 12 import android.widget.TableLayout; 13 import android.widget.TableRow; 14 import android.widget.TextView; 15 import android.widget.Toast; 16 17 18 public class MainActivity extends Activity { 19 private TextView text_column; 20 private TextView text_row ; 21 private TableLayout tabLay; 22 private int length = 64; 23 @Override 24 protected void onCreate(Bundle savedInstanceState) { 25 super.onCreate(savedInstanceState); 26 setContentView(R.layout.layout2); 27 //获取控件按钮 28 Button btn_commit = (Button) findViewById(R.id.btn_commit); 29
//获取控件textview 30 text_column = (TextView) findViewById(R.id.text_column); 31 text_row= (TextView) findViewById(R.id.text_row); 32 33 //给按钮设置点击事件 34 btn_commit.setOnClickListener(new OnClickListener(){ 35 36 @Override 37 public void onClick(View v) { 38
//获取文本值 39 String column = text_column.getText().toString().trim(); 40 String row = text_row.getText().toString().trim(); 41 //判断是否为空 42 if(column.length() != 0 && row.length() != 0){ 43 //获取控件布局 44 tabLay= (TableLayout) findViewById(R.id.tablelayout); 45 46 //先清空 47 tabLay.removeAllViewsInLayout(); 48 tabLay.setStretchAllColumns(true); 49 //强转整型 50 int x =Integer.parseInt(text_column.getText().toString()); //?? 51 int y =Integer.parseInt(text_row.getText().toString()); 52 53 54 //for循环嵌套 55 for(int m = 0 ; m < y; m++ ){ 56 57 TableRow tr = new TableRow(MainActivity.this); 58 59 for(int n = 0 ; n < x ; n++ ){ 60 61 TextView tv = new TextView(MainActivity.this); 62 63 //tv.setText("("+n+","+m+")"); 64 tv.setText(" "); 65 tr.addView(tv); 66 //获取参数,设置背景颜色值 67 int result = m*n +2*n-1; 68 int red = result / 16/16 ; 69 int green = ( result - red*16*16)/16; 70 int blue = result - red*16*16 - green*16; 71 72 tv.setBackgroundColor(Color.rgb(red*16, green*16, blue*16)); 73 74 75 } 76 tabLay.addView(tr); 77 78 } 79 80 }else{ 81 Toast.makeText(MainActivity.this,"请输入行和列",1).show(); 82 } 83 } 84 }); 85 86 } 87 }