My android plotting learning notes (1)

2010-11-04

I plan to draw a coordinate axis, draw a line chart, and draw a coordinate axis with a straight line at the beginning, but it is not very nice.

First paste the code

/** Testpaint. Java **/

package com.test;import android.app.Activity;import android.content.Context;import android.graphics.Canvas;import android.graphics.Color;import android.graphics.Paint;import android.os.Bundle;import android.view.View;public class testPaint extends Activity { /** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) {  super.onCreate(savedInstanceState);  MyView myview = new MyView(this);  setContentView(myview); } private class MyView extends View {  @Override  protected void onDraw(Canvas canvas) {   super.onDraw(canvas);   canvas.drawColor(Color.WHITE);   Paint paint =new Paint();   paint.setAntiAlias(true);   paint.setColor(Color.BLACK);   Paint paint1=new Paint();   paint1.setColor(Color.RED);   canvas.drawLine(30, 160, 300, 160, paint);   canvas.drawLine(30, 160, 30, 30, paint);   canvas.drawLine(30, 30, 24, 36, paint);   canvas.drawLine(30, 30, 36, 36, paint);   canvas.drawLine(300, 160, 294, 154, paint);   canvas.drawLine(300, 160,294, 166, paint);   paint.setTextSize(12);   canvas.drawText(getResources().getString(R.string.date), 280, 180,     paint);   canvas.drawText(getResources().getString(R.string.product), 1, 40, paint);  }  public MyView(Context context) {   super(context);  } }}

/** Strings. xml */

<? XML version = "1.0" encoding = "UTF-8"?> <Resources> <string name = "hello"> Hello world, testpaint! </String> <string name = "app_name"> testpaint </string> <string name = "date"> day </string> <string name = "product"> output </string> </resources>

 

Running Effect

 

Then I found a polygon Filling Method to draw arrows.

 

/** Testpaint. Java */

package com.test;import android.app.Activity;import android.content.Context;import android.graphics.Canvas;import android.graphics.Color;import android.graphics.Paint;import android.graphics.Path;import android.os.Bundle;import android.view.View;public class testPaint extends Activity { /** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) {  super.onCreate(savedInstanceState);  MyView myview = new MyView(this);  setContentView(myview); } private class MyView extends View {  @Override  protected void onDraw(Canvas canvas) {   super.onDraw(canvas);   canvas.drawColor(Color.WHITE);   Paint paint =new Paint();   paint.setAntiAlias(true);   paint.setColor(Color.BLACK);   Paint paint1=new Paint();   paint1.setColor(Color.RED);   canvas.drawLine(30, 160, 300, 160, paint);   canvas.drawLine(30, 160, 30, 30, paint);   Path path=new Path();   path.moveTo(30, 30);   path.lineTo(25,35);   path.lineTo(30, 25);   path.lineTo(35, 35);   canvas.drawPath(path, paint);      Path path1=new Path();   path1.moveTo(300, 160);   path1.lineTo(295,155);   path1.lineTo(305, 160);   path1.lineTo(295, 165);   canvas.drawPath(path1, paint);      paint.setTextSize(12);   canvas.drawText(getResources().getString(R.string.date), 280, 180,     paint);   canvas.drawText(getResources().getString(R.string.product), 1, 40, paint);  }  public MyView(Context context) {   super(context);  } }}

 

Running Effect

 

This looks much better, haha