android画图实例_[调用资源_画图]

1 主要有三个按钮一个imageview三个功能

package com.example.b;import android.app.Activity;import android.os.Bundle;import android.content.res.Resources;import android.graphics.Bitmap;import android.graphics.Bitmap.Config;import android.graphics.BitmapFactory;import android.graphics.Canvas;import android.graphics.Color;import android.graphics.Paint;import android.graphics.Typeface;import android.graphics.drawable.BitmapDrawable;import android.graphics.drawable.Drawable;import android.os.Bundle;import android.view.View;import android.widget.Button;import android.widget.ImageView;public class DrawActivity extends Activity {ImageView iv;Button btn1, btn2, btn3, btn4;Resources r;@Overridepublic void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.paint);iv = (ImageView) this.findViewById(R.id.ImageView01);btn1 = (Button) this.findViewById(R.id.Button01);btn2 = (Button) this.findViewById(R.id.Button02);btn3 = (Button) this.findViewById(R.id.Button03);btn1.setOnClickListener(new ClickEvent());btn2.setOnClickListener(new ClickEvent());btn3.setOnClickListener(new ClickEvent());r = this.getResources();}class ClickEvent implements View.OnClickListener {public void onClick(View v) {if (v == btn1)// 显示资源图片{// 功能等效// iv.setBackgroundResource(R.drawable.icon);//打开资源图片Bitmap bmp = BitmapFactory.decodeResource(r, R.drawable.icon);// 打开资源图片iv.setImageBitmap(bmp);} else if (v == btn2)// 显示并绘画资源图片{Bitmap bmp = BitmapFactory.decodeResource(r, R.drawable.icon);// 只读,不能直接在bmp上画Bitmap newb = Bitmap.createBitmap(300, 300, Config.ARGB_8888);Canvas canvasTemp = new Canvas(newb);canvasTemp.drawColor(Color.TRANSPARENT);Paint p = new Paint();String familyName = "宋体";Typeface font = Typeface.create(familyName, Typeface.BOLD);p.setColor(Color.RED);p.setTypeface(font);p.setTextSize(22);canvasTemp.drawText("写字。。。", 50, 50, p);canvasTemp.drawBitmap(bmp, 50, 50, p);// 画图iv.setImageBitmap(newb);} else if (v == btn3)// 直接在Button上绘图{Bitmap newb = Bitmap.createBitmap(btn3.getWidth(),btn3.getHeight(), Config.ARGB_8888);Canvas canvasTemp = new Canvas(newb);canvasTemp.drawColor(Color.WHITE);Paint p = new Paint();String familyName = "宋体";Typeface font = Typeface.create(familyName, Typeface.BOLD);p.setColor(Color.RED);p.setTypeface(font);p.setTextSize(20);canvasTemp.drawText("写字。。。", 30, 30, p);Drawable drawable = new BitmapDrawable(newb);btn3.setBackgroundDrawable(drawable);}}}}

2

<?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" >    <Button android:id="@+id/Button01" android:layout_width="fill_parent" android:layout_height="44px" android:text="显示资源图片"></Button>  <Button android:id="@+id/Button02" android:layout_width="fill_parent" android:layout_height="44px" android:text="显示并绘画资源图片"></Button>  <Button android:id="@+id/Button03" android:layout_height="44px" android:layout_width="fill_parent" android:text="在控件上绘图"></Button>  <ImageView android:id="@+id/ImageView01" android:layout_width="wrap_content" android:layout_height="wrap_content"></ImageView>  </LinearLayout>

3 结果