Android描画简单圆形
最近又变成android开发了。。。上网看了本书,研究了下。。。其实,从qt过渡到android,虽说用的函数不一样。感觉思路都差不多呢。。。。
在activicy中布局:
<?xml version="1.0" encoding="utf-8"?> <androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:app="http://schemas.android.com/apk/res-auto" xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent" android:layout_height="match_parent" tools:context=".MainActivity"> <ImageView android:id="@+id/iv" android:layout_width="match_parent" android:layout_height="match_parent" /> </androidx.constraintlayout.widget.ConstraintLayout>
在MainActivity.java中添加如下代码:
package leavesc.hello.text_canvas; import androidx.appcompat.app.AppCompatActivity; import android.graphics.Bitmap; import android.graphics.BitmapFactory; import android.graphics.Canvas; import android.graphics.Color; import android.graphics.Paint; import android.graphics.Rect; import android.graphics.RectF; import android.os.Bundle; import android.widget.ImageView; public class MainActivity extends AppCompatActivity { private ImageView iv; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); iv = (ImageView)findViewById(R.id.iv); Bitmap bmpBuffer = Bitmap.createBitmap(500,800,Bitmap.Config.ARGB_8888); Canvas canvas = new Canvas(bmpBuffer); Paint paint = new Paint(); paint.setStyle(Paint.Style.STROKE); RectF rect = new RectF(10,10,400,400); paint.setColor(Color.GRAY); canvas.drawOval(rect, paint); paint.setAntiAlias(true); paint.setColor(Color.GREEN); paint.setStyle(Paint.Style.STROKE); paint.setStrokeWidth(3); canvas.drawArc(rect, -90, 90, false, paint); iv.setImageBitmap(bmpBuffer); } }
如果能加上java的timer使其动态描画就能得到圆形进度条的效果了。应该是这个思路吧