我尝试过实施拖拽方法在屏幕上放置一个位图。当卡片是一个imageView和XML文件时，我试过的方法工作了，但我改变了我的方法，我只是在调用draw方法时将位图加载到屏幕上。
有人可以告诉我实现拖放加载到屏幕上的位图的最佳方法吗？提前谢谢。
我的代码： 播放屏幕类:(位图加载并绘制到屏幕上）
package com.example.llave_000.shootout.screens;
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Matrix;
import android.graphics.PointF;
import android.graphics.Rect;
import android.graphics.RectF;
import android.view.MotionEvent;
import android.view.ScaleGestureDetector;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ImageView;
import android.widget.RelativeLayout;
import android.view.View.OnTouchListener;
import com.example.llave_000.shootout.Game;
import com.example.llave_000.shootout.MoveGestureDetector;
import com.example.llave_000.shootout.R;
import com.example.llave_000.shootout.Settings.Settings;
import com.example.llave_000.shootout.engine.AssetStore;
import com.example.llave_000.shootout.engine.ElapsedTime;
import com.example.llave_000.shootout.engine.audio.Music;
import com.example.llave_000.shootout.engine.graphics.IGraphics2D;
import com.example.llave_000.shootout.engine.input.Input;
import com.example.llave_000.shootout.engine.input.TouchEvent;
import com.example.llave_000.shootout.world.GameObject;
import com.example.llave_000.shootout.world.GameScreen;
import com.example.llave_000.shootout.world.LayerViewport;
import com.example.llave_000.shootout.world.ScreenViewport;
import java.util.List;
import static com.example.llave_000.shootout.R.id.imageView;
public class PlayScreen extends GameScreen {
// /////////////////////////////////////////////////////////////////////////
// Properties
// /////////////////////////////////////////////////////////////////////////
private Rect backButtonBound;
private Rect hazardCardBound;
private Music screenClickMusic;
/**
* Width and height of the level
*/
// private final float LEVEL_WIDTH = 1000.0f;
//private final float LEVEL_HEIGHT = 1000.0f;
/**
* Define viewports for this layer and the associated screen projection
*/
private ScreenViewport mScreenViewport;
private LayerViewport mLayerViewport;
private Bitmap backgroundBitmap;
private Bitmap backButton;
private Bitmap PlayScreenTitle;
private Bitmap hazardCard;
private Rect frontLayerBound;
private Rect playScreenTitleBound;
private ImageView cardImage1;
private ViewGroup rootLayout;
private int _xDelta;
private int _yDelta;
public View view;
/**
* User input controls for managing the player and the game
*/
// protected InputControl pauseButton
// /////////////////////////////////////////////////////////////////////////
// Constructors
// /////////////////////////////////////////////////////////////////////////
/**
* Create a game
*
* @param game
* Game to which this screen belongs */
public PlayScreen(Game game) {
super("PlayScreen", game);
//Define the rects what will be used to 'hold' the images
int spacingX = game.getScreenWidth() / 8;
int spacingY = game.getScreenHeight() / 8;
int padding = spacingY / 10; //padding between each button
int line = 1; //each button is on a new 'line' (under each other)
// Load in the assets used by the demo
AssetStore assetManager = game.getAssetManager();
assetManager.loadAndAddBitmap("pitch", "img/pitch.png");
assetManager.loadAndAddBitmap("backButton", "img/back_button.png");
assetManager.loadAndAddBitmap("hazardCard", "img/hazard_card.jpg");
// Define Rectangles for Bitmaps
// playScreenTitleBound = new Rect(spacingX * 2, spacingY * 0, spacingX * 6, spacingY * 1);
this.backgroundBitmap = assetManager.getBitmap("pitch");
this.backButton = assetManager.getBitmap("backButton");
this.hazardCard = assetManager.getBitmap("hazardCard");
//load in sounds
assetManager.loadAndAddMusic("screenClickMusic", "music/buttonPress.mp3");
//initialise
this.screenClickMusic = assetManager.getMusic("screenClickMusic");
}
// /////////////////////////////////////////////////////////////////////////
// Support methods
// /////////////////////////////////////////////////////////////////////////
// /////////////////////////////////////////////////////////////////////////
// Update and Draw methods
// /////////////////////////////////////////////////////////////////////////
@Override
public void update(ElapsedTime elapsedTime) {
//process any touch events occurring since the update
Input input = game.getInput();
List<TouchEvent> touchEvents = input.getTouchEvents();
if (touchEvents.size() > 0) {
//Just check the first touch event that occurred in the frame.
//It means pressing the screen with several fingers may not
//trigger a 'button'.
TouchEvent touchEvent = touchEvents.get(0);
if (backButtonBound.contains((int) touchEvent.x, (int) touchEvent.y)
&& touchEvent.type == TouchEvent.TOUCH_UP) {
// If the play game area has been touched then swap screens
game.getScreenManager().removeScreen(this.getName());
MenuScreen menuScreen = new MenuScreen(game);
if (Settings.soundEnabled) {
screenClickMusic.play();
}
// As it's the only added screen it will become active.
game.getScreenManager().addScreen(menuScreen);
}
/*else if (hazardCardBound.contains((int) touchEvent.x, (int) touchEvent.y)
&& touchEvent.type == TouchEvent.TOUCH_DOWN) {
RelativeLayout.LayoutParams lparams = (RelativeLayout.LayoutParams) view.getLayoutParams();
_xDelta = X - lparams.leftMargin;
_yDelta = Y - lparams.topMargin;
}*/
}
}
@Override
public void draw(ElapsedTime elapsedTime, IGraphics2D graphics2D) {
// load hazard playing card
/*ImageView hazardCardImageView = (ImageView) view.findViewById(R.id.hazardCardImageView);
if (hazardCard != null) {
hazardCardImageView.setImageBitmap(hazardCard);
}
cardImage1 = (ImageView) rootLayout.findViewById(R.id.hazardCardImageView);
RelativeLayout.LayoutParams layoutParams = new RelativeLayout.LayoutParams(500, 150);
cardImage1.setLayoutParams(layoutParams);
cardImage1.setOnTouchListener(new ChoiceTouchListener());*/
// Get and draw the bitmaps into the defined rectangles
Bitmap backButton = game.getAssetManager().getBitmap("backButton");
// Create the screen to black and define a clip based on the viewport
graphics2D.clear(Color.BLACK);
//graphics2D.clipRect(mScreenViewport.toRect());
// Define the rects what will be used to 'hold' the images
int spacingX = game.getScreenWidth() / 8;
int spacingY = game.getScreenHeight() / 8;
int padding = spacingY / 10; //padding between each button
int line = 1; //each button is on a new 'line' (under each other)
hazardCardBound = new Rect(spacingX, spacingY * 2 + padding, spacingX * 7, spacingY * 3);
if (frontLayerBound == null) {
frontLayerBound = new Rect(0, 0, graphics2D.getSurfaceWidth(),
graphics2D.getSurfaceHeight());
}
if (backButtonBound == null) {
int left = 10;
int bottom = (graphics2D.getSurfaceHeight() - 120);
backButtonBound = new Rect(left, bottom, left + 100, bottom + 120);
}
//cardImage1 = (ImageView)view.findViewById(R.id.hazardCardImageView);
/* RelativeLayout.LayoutParams layoutParams = new RelativeLayout.LayoutParams(500, 150);
cardImage1.setLayoutParams(layoutParams);
cardImage1.setOnTouchListener(new ChoiceTouchListener());
cardImage1.setOnTouchListener(new ChoiceTouchListener());
cardImage1.setImageBitmap(hazardCard);*/
// RelativeLayout.LayoutParams layoutParams = new RelativeLayout.LayoutParams(500, 150);
//draw bitmaps with relative bounds
graphics2D.drawBitmap(backgroundBitmap, null, frontLayerBound,null);
graphics2D.drawBitmap(backButton, null, backButtonBound, null);
graphics2D.drawBitmap(hazardCard,null, hazardCardBound, null);
// RelativeLayout.LayoutParams layoutParams = new RelativeLayout.LayoutParams(500, 150);
// cardImage1.setLayoutParams(layoutParams);
// cardImage1.setImageBitmap(hazardCard);
//cardImage1.setOnTouchListener(new ChoiceTouchListener());
}
/* @Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
View view = inflater.inflate(R.layout.fragment_play_screen, container, false);
FragmentManager fm = getFragmentManager();
Fragment fragment = fm.findFragmentById(R.id.fragment_play_screen);
if (fragment == null) {
// Log.d("","@ PLAY SCREEN"); --logcat shows execution reaches this point
fragment = createFragment();
fm.beginTransaction().add(R.id.fragment_play_screen, fragment)
.commit();
}
AssetManager assetManager = getActivity().getAssets();
Bitmap backButton = loadBitmap(assetManager, "img/back_button.png");
ImageView backButtonimageView = (ImageView) view.findViewById(R.id.backButton);
if (backButton != null) {
backButtonimageView.setImageBitmap(backButton);
}
backButtonimageView.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
Log.d("BACK BUTTON CLICKED", "BACK BUTTON CLICKED");
FragmentTransaction transaction = getFragmentManager().beginTransaction();
//go back to main menu screen
transaction.replace(R.id.fragment_play_screen, new MenuScreen());
transaction.addToBackStack(null);
// Commit the transaction
transaction.commit();
}
});
private Layer target;
}
class Layer {
Matrix matrix = new Matrix();
Matrix inverse = new Matrix();
RectF bounds;
View parent;
Bitmap bitmap;
MoveGestureDetector mgd;
public Layer(Context ctx, View p, Bitmap b) {
parent = p;
bitmap = b;
bounds = new RectF(0, 0, b.getWidth(), b.getHeight());
mgd = new MoveGestureDetector(ctx, mgl);
matrix.postTranslate(50 + (float) Math.random() * 50, 50 + (float) Math.random() * 50);
}
public boolean contains(MotionEvent event) {
matrix.invert(inverse);
float[] pts = {event.getX(), event.getY()};
inverse.mapPoints(pts);
if (!bounds.contains(pts[0], pts[1])) {
return false;
}
return Color.alpha(bitmap.getPixel((int) pts[0], (int) pts[1])) != 0;
}
public boolean onTouchEvent(MotionEvent event) {
mgd.onTouchEvent(event);
return true;
}
public void draw(Canvas canvas) {
canvas.drawBitmap(bitmap, matrix, null);
}
MoveGestureDetector.SimpleOnMoveGestureListener mgl = new MoveGestureDetector.SimpleOnMoveGestureListener() {
@Override
public boolean onMove(MoveGestureDetector detector) {
PointF delta = detector.getFocusDelta();
matrix.postTranslate(delta.x, delta.y);
parent.invalidate();
return true;
}
};
}
IGraphics2D课程：
/**
* The graphics 2D interface defines the set of graphical operations that can be
* applied to a render surface.
*
* @version 1.0
*/
public interface IGraphics2D {
/**
* Get the width of the render surface
*
* @return Width of the render surface
*/
public int getSurfaceWidth();
/**
* Get the height of the render surface
*
* @return Height of the render surface
*/
public int getSurfaceHeight();
/**
* Insert the specified rectangular clip region
*
* @param clipRegion
*/
public void clipRect(Rect clipRegion);
/**
* Set the surface colour to that specified colour (assumed to be in the
* same format as the Color class - ARGB).
*
* @param colour
* ARGB formatted colour
*/
public void clear(int colour);
/**
* Draw the specified text string
*
* @param text
* String of text to be rendered
* @param x
* Location of text on x-axis
* @param y
* Location of text on y-axis
* @param paint
* Paint parameters controlling text render format
*/
public void drawText(String text, float x, float y, Paint paint);
/**
* Draw the specified bitmap
*
* @param bitmap
* Bitmap to be rendered
* @param srcRect
* Source region to be rendered (if null full source is rendered)
* @param desRect
* Destination region for the render
* @param paint
* Paint parameters controlling how the bitmap is rendered
*/
public void drawBitmap(Bitmap bitmap, Rect srcRect, Rect desRect,
Paint paint);
/**
* Draw the specified bitmap
*
* @param bitmap
* Bitmap to be rendered
* @param matrix
* Matrix defining bitmap scaling, rotation, translation, etc.
* @param paint
* Paint parameters controlling how the bitmap is rendered
*/
public void drawBitmap(Bitmap bitmap, Matrix matrix, Paint paint);
}
编辑： 有效的方法是使用这个：
RelativeLayout.LayoutParams layoutParams = new RelativeLayout.LayoutParams(500, 150);
cardImage.setLayoutParams(layoutParams);
cardImage.setOnTouchListener(new ChoiceTouchListener());
//load hazard playing card
Bitmap hazardCard = loadBitmap(assetManager, "img/hazard_card.jpg");
ImageView hazardCardimageView = (ImageView) view.findViewById(R.id.hazardCardImageView);
if (hazardCard != null) {
hazardCardimageView.setImageBitmap(hazardCard);
}
private final class ChoiceTouchListener implements View.OnTouchListener {
public boolean onTouch(View view, MotionEvent event) {
final int X = (int) event.getRawX();
final int Y = (int) event.getRawY();
switch (event.getAction() & MotionEvent.ACTION_MASK) {
case MotionEvent.ACTION_DOWN:
RelativeLayout.LayoutParams lparams = (RelativeLayout.LayoutParams) view.getLayoutParams();
_xDelta = X - lparams.leftMargin;
_yDelta = Y - lparams.topMargin;
break;
case MotionEvent.ACTION_UP:
break;
case MotionEvent.ACTION_POINTER_DOWN:
break;
case MotionEvent.ACTION_POINTER_UP:
break;
case MotionEvent.ACTION_MOVE:
RelativeLayout.LayoutParams layoutParams = (RelativeLayout.LayoutParams) view.getLayoutParams();
layoutParams.leftMargin = X - _xDelta;
layoutParams.topMargin = Y - _yDelta;
layoutParams.rightMargin = 0b11111111111111111111111100000110;
layoutParams.bottomMargin = 0b11111111111111111111111100000110;
view.setLayoutParams(layoutParams);
break;
}
rootLayout.invalidate();
return true;
}
}
主要活动类： package com.example.llave_000.shootout;
import android.app.Activity;
import android.app.FragmentManager;
import android.graphics.PointF;
import android.os.Bundle;
import android.view.MotionEvent;
import android.view.ScaleGestureDetector;
import android.view.View;
import android.view.ViewGroup;
import android.view.Window;
import android.view.WindowManager;
import com.example.llave_000.shootout.world.DemoGame;
import com.example.llave_000.shootout.BaseGestureDetector;
import com.example.llave_000.shootout.MoveGestureDetector;
import android.widget.ImageView;
public class MainActivity extends Activity implements View.OnTouchListener {
private float mScaleFactor = 1.0f;
private float mRotationDegrees = 0.f;
private float mFocusX = 0.f;
private float mFocusY = 0.f;
private ImageView cardImage1;
private ViewGroup rootLayout;
public View view;
private MoveGestureDetector mMoveDetector;
private ScaleGestureDetector mScaleDetector;
/* private RotationGestureDetector mRotateDetector;
private MoveGestureDetector mMoveDetector;*/
/**
* Game fragment instance
*/
private Game mGame;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
//ImageView hazardCardImageView = (ImageView) view.findViewById(R.id.hazardCardImageView);
cardImage1 = (ImageView)findViewById(R.id.hazardCardImageView);
// Setup Gesture Detectors
mMoveDetector = new MoveGestureDetector(getApplicationContext(), new MoveListener());
//mScaleDetector = new ScaleGestureDetector(getApplicationContext(), new ScaleListener());
/*mRotateDetector = new RotationGestureDetector(getApplicationContext(), new RotateListener());
mMoveDetector = new MoveGestureDetector(getApplicationContext(), new MoveListener());*/
// Setup the window as suitable for a game, namely: full screen
// with no title and a request to keep the screen on. The changes
// are made before any content is inflated.
Window window = getWindow();
window.requestFeature(Window.FEATURE_NO_TITLE);
window.addFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN);
window.addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);
// Set the content view to use a simple frame layout
setContentView(R.layout.activity_main);
// Add in the main game fragment..
FragmentManager fm = getFragmentManager();
// MenuScreen menuScreen = (MenuScreen)fm.findFragmentById(R.id.activity_main_id);
mGame = (Game)fm.findFragmentById(R.id.activity_main_id);
if (mGame == null) {
mGame = new DemoGame(); //not sure if correct
fm.beginTransaction().add(R.id.activity_main_id, mGame)
.commit();
}
// Add in the main game fragment
/* if (savedInstanceState == null) {
getFragmentManager().beginTransaction()
.add(R.id.activity_main_id, new MenuScreen()).commit();
}*/
}
public boolean onTouch(View view, MotionEvent event) {
mScaleDetector.onTouchEvent(event);
mMoveDetector.onTouchEvent(event);
/* mRotateDetector.onTouchEvent(event);
mMoveDetector.onTouchEvent(event);
*/
// Mmmmmhhhagic!!!
// with: mScaleFactor, mRotationDegrees, mFocusX and mFocusY
return true; // indicate event was handled
}
private class ScaleListener extends ScaleGestureDetector.SimpleOnScaleGestureListener {
@Override
public boolean onScale(ScaleGestureDetector detector) {
mScaleFactor *= detector.getScaleFactor(); // scale change since previous event
return true;
}
}
/* private class RotateListener extends RotateGestureDetector.SimpleOnRotateGestureListener {
@Override
public boolean onRotate(RotateGestureDetector detector) {
mRotationDegrees -= detector.getRotationDegreesDelta();
return true;
}
}
*/
private class MoveListener extends MoveGestureDetector.SimpleOnMoveGestureListener {
@Override
public boolean onMove(MoveGestureDetector detector) {
PointF d = detector.getFocusDelta();
mFocusX += d.x;
mFocusY += d.y;
return true;
}
}
@Override
public void onBackPressed() {
// If the fragment does not consume the back event then
// trigger the default behaviour
if(!mGame.onBackPressed())
super.onBackPressed();
}
/* public boolean onTouchEvent(MotionEvent me) {
if (me.getAction() == MotionEvent.ACTION_DOWN) {
//code in here to take me to new screen with match attax background
//with new screen displaying a card. then work on being able to move that card.
//playButtonY -= 20;
}*/
// playButton.setY(playButtonY);
//code in here to take me to new screen with match attax background
//with new screen displaying a card. then work on being able to move that card.
//return true;
}
...