activity_main.xml
<?xml version="1.0" encoding="utf-8"?> <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools" android:id="@+id/rl" android:layout_width="match_parent" android:layout_height="match_parent" android:padding="16dp" tools:context=".MainActivity" android:background="#b4b9cc" > <ImageView android:id="@+id/iv" android:layout_width="wrap_content" android:layout_height="wrap_content" /> <Button android:id="@+id/btn" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Draw" android:layout_alignParentRight="true" android:layout_alignParentEnd="true" android:layout_alignParentBottom="true" /> </RelativeLayout> MainActivity.java
package com.cfsuman.me.androidcode; import android.content.Context; import android.content.res.Resources; import android.graphics.Color; import android.graphics.Paint; import android.support.v7.app.AppCompatActivity; import android.os.Bundle; import android.view.View; import android.widget.Button; import android.widget.ImageView; import android.widget.RelativeLayout; import android.graphics.Canvas; import android.graphics.Bitmap; public class MainActivity extends AppCompatActivity { private Context mContext; private Resources mResources; private RelativeLayout mRelativeLayout; private Button mButton; private ImageView mImageView; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); // Get the application context mContext = getApplicationContext(); // Get the Resources mResources = getResources(); // Get the widgets reference from XML layout mRelativeLayout = (RelativeLayout) findViewById(R.id.rl); mButton = (Button) findViewById(R.id.btn); mImageView = (ImageView) findViewById(R.id.iv); // Set a click listener for Button widget mButton.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View view) { // Initialize a new Bitmap Bitmap bitmap = Bitmap.createBitmap( 600, // Width 300, // Height Bitmap.Config.ARGB_8888 // Config ); // Initialize a new Canvas instance Canvas canvas = new Canvas(bitmap); // Draw a solid color on the canvas as background canvas.drawColor(Color.YELLOW); // Initialize a new Paint instance to draw on canvas Paint paint = new Paint(); paint.setStyle(Paint.Style.FILL); paint.setColor(Color.RED); paint.setAntiAlias(true); // Set an offset value in pixels to draw rectangle on canvas int offset = 100; /* public int save (int saveFlags) Based on saveFlags, can save the current matrix and clip onto a private stack. Note: if possible, use the parameter-less save(). It is simpler and faster than individually disabling the saving of matrix or clip with this method. Subsequent calls to translate,scale,rotate,skew,concat or clipRect, clipPath will all operate as usual, but when the balancing call to restore() is made, those calls will be forgotten, and the settings that existed before the save() will be reinstated. Parameters saveFlags : flag bits that specify which parts of the Canvas state to save/restore Returns The value to pass to restoreToCount() to balance this save() */ /* MATRIX_SAVE_FLAG Restore the current matrix when restore() is called. */ // Save the canvas state canvas.save(Canvas.MATRIX_SAVE_FLAG); /* public jawaban void rotate (float degrees, float px, float py) Preconcat the current matrix with the specified rotation. Parameters degrees : The amount to rotate, in degrees px : The x-coord for the pivot point (unchanged by the rotation) py : The y-coord for the pivot point (unchanged by the rotation) */ // Rotate the canvas canvas.rotate( 25, // degrees canvas.getWidth() / 2, // px, center x canvas.getHeight() / 2 // py, center y ); // Draw the rounded corners rectangle object on the canvas // The rectangle will be drawn as a 25 degrees rotated rectangle canvas.drawRect( offset, // left offset, // top canvas.getWidth() - offset, // right canvas.getHeight() - offset, // bottom paint // Paint ); /* public void restore () This call balances a previous call to save(), and is used to remove all modifications to the matrix/clip state since the last save call. It is an error to call restore() more times than save() was called. */ // Finally, restore the canvas state canvas.restore(); // Display the newly created bitmap on app interface mImageView.setImageBitmap(bitmap); } }); } } 
- How to create layout tiled background
- How to create LayerDrawable programmatically
- How to draw a circle on a canvas
- How to draw a rectangle on a canvas
- How to draw a line on canvas
- How to draw a bitmap on a canvas
- How to draw a rounded rectangle on canvas
- How to rotate a bitmap on canvas center
- How to use custom font in TextView
- How to get TextView width and height
Komentar
Posting Komentar