我正在使用Github library中的Glide和CircularImageview来获取图像URL并将其显示到Drawerlayout的{{1}}中。它工作正常，并且图像已加载。当我打开应用程序并关闭应用程序而不打开ImageView时，它不会产生任何错误，但是当我打开应用程序并打开NavigationDrawer并按返回按钮以关闭应用程序时，它崩溃以下错误：
DrawerLayout我的导航抽屉方法是
Process: com.mscphysics.plusacademy, PID: 21955
java.lang.RuntimeException: Unable to destroy activity {com.mscphysics.plusacademy/com.mscphysics.plusacademy.PaidUser.Activity.Home}: java.lang.NullPointerException
at android.app.ActivityThread.performDestroyActivity(ActivityThread.java:3498)
at android.app.ActivityThread.handleDestroyActivity(ActivityThread.java:3516)
at android.app.ActivityThread.access$1400(ActivityThread.java:135)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1249)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:136)
at android.app.ActivityThread.main(ActivityThread.java:5018)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:515)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:785)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:601)
at dalvik.system.NativeStart.main(Native Method)
Caused by: java.lang.NullPointerException
at android.graphics.Bitmap.createScaledBitmap(Bitmap.java:589)
at com.pkmmte.view.CircularImageView.refreshBitmapShader(CircularImageView.java:341)
at com.pkmmte.view.CircularImageView.invalidate(CircularImageView.java:262)
at android.widget.ImageView.setImageDrawable(ImageView.java:426)
at com.bumptech.glide.request.target.DrawableImageViewTarget.setResource(DrawableImageViewTarget.java:28)
at com.bumptech.glide.request.target.DrawableImageViewTarget.setResource(DrawableImageViewTarget.java:10)
at com.bumptech.glide.request.target.ImageViewTarget.setResourceInternal(ImageViewTarget.java:127)
at com.bumptech.glide.request.target.ImageViewTarget.onLoadCleared(ImageViewTarget.java:97)
at com.bumptech.glide.request.SingleRequest.clear(SingleRequest.java:319)
at com.bumptech.glide.manager.RequestTracker.clearRemoveAndMaybeRecycle(RequestTracker.java:79)
at com.bumptech.glide.manager.RequestTracker.clearRemoveAndRecycle(RequestTracker.java:66)
at com.bumptech.glide.RequestManager.untrack(RequestManager.java:603)
at com.bumptech.glide.RequestManager.untrackOrDelegate(RequestManager.java:571)
at com.bumptech.glide.RequestManager.clear(RequestManager.java:559)
at com.bumptech.glide.RequestManager.onDestroy(RequestManager.java:303)
at com.bumptech.glide.manager.ActivityFragmentLifecycle.onDestroy(ActivityFragmentLifecycle.java:65)
at com.bumptech.glide.manager.SupportRequestManagerFragment.onDestroy(SupportRequestManagerFragment.java:194)
at android.support.v4.app.Fragment.performDestroy(Fragment.java:2588)
at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1566)
at android.support.v4.app.FragmentManagerImpl.moveFragmentToExpectedState(FragmentManager.java:1759)
at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1827)
at android.support.v4.app.FragmentManagerImpl.dispatchStateChange(FragmentManager.java:3244)
at android.support.v4.app.FragmentManagerImpl.dispatchDestroy(FragmentManager.java:3235)
at android.support.v4.app.FragmentController.dispatchDestroy(FragmentController.java:265)
at android.support.v4.app.FragmentActivity.onDestroy(FragmentActivity.java:390)
at android.support.v7.app.AppCompatActivity.onDestroy(AppCompatActivity.java:209)
at android.app.Activity.performDestroy(Activity.java:5410)
at android.app.Instrumentation.callActivityOnDestroy(Instrumentation.java:1117)
at android.app.ActivityThread.performDestroyActivity(ActivityThread.java:3485)
at android.app.ActivityThread.handleDestroyActivity(ActivityThread.java:3516)
at android.app.ActivityThread.access$1400(ActivityThread.java:135)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1249)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:136)
at android.app.ActivityThread.main(ActivityThread.java:5018)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:515)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:785)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:601)
at dalvik.system.NativeStart.main(Native Method)
我的xml是
public void updateNavHeader() {
NavigationView navigationView = (NavigationView) findViewById(R.id.nav_view);
View headerView = navigationView.getHeaderView(0);
TextView navUsername = headerView.findViewById(R.id.nav_username);
TextView navUserMail = headerView.findViewById(R.id.nav_user_mail);
ImageView navUserPhot = headerView.findViewById(R.id.nav_user_photo);
navUserMail.setText(currentUser.getEmail());
navUsername.setText(currentUser.getDisplayName());
// now we will use Glide to load user image
// first we need to import the library
Glide.with(this).load(currentUser.getPhotoUrl()).into(navUserPhot);
}
任何人都可以解释为什么在打开应用程序时以及在打开导航抽屉并关闭应用程序后会引发错误，但不能解释为什么仅打开应用程序而只是不打开抽屉就将其关闭。
答案 0 :(得分：1)
请改用此CircleImageView library。 这是我在许多项目中看到的用于圆形图像的库 这应该可以解决您的问题
这是一个例子
<de.hdodenhof.circleimageview.CircleImageView
xmlns:app="http://schemas.android.com/apk/res-auto"
android:id="@+id/profile_image"
android:layout_width="96dp"
android:layout_height="96dp"
android:src="@drawable/profile"
app:civ_border_width="2dp"
app:civ_border_color="#FF000000"/>
答案 1 :(得分：0)
我有一个使图像圆形的类，我不知道从何处获得图像，但是它与Glide配合得很好
import android.content.Context;
import android.content.res.TypedArray;
import android.graphics.Bitmap;
import android.graphics.BitmapShader;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.ColorFilter;
import android.graphics.Matrix;
import android.graphics.Paint;
import android.graphics.RectF;
import android.graphics.Shader;
import android.graphics.drawable.BitmapDrawable;
import android.graphics.drawable.ColorDrawable;
import android.graphics.drawable.Drawable;
import android.net.Uri;
import android.util.AttributeSet;
import androidx.annotation.ColorInt;
import androidx.annotation.ColorRes;
import androidx.annotation.DrawableRes;
import androidx.appcompat.widget.AppCompatImageView;
public class CircleImageView extends AppCompatImageView {
private static final ScaleType SCALE_TYPE = ScaleType.CENTER_CROP;
private static final Bitmap.Config BITMAP_CONFIG = Bitmap.Config.ARGB_8888;
private static final int COLORDRAWABLE_DIMENSION = 2;
private static final int DEFAULT_BORDER_WIDTH = 0;
private static final int DEFAULT_BORDER_COLOR = Color.BLACK;
private static final int DEFAULT_FILL_COLOR = Color.TRANSPARENT;
private static final boolean DEFAULT_BORDER_OVERLAY = false;
private final RectF mDrawableRect = new RectF();
private final RectF mBorderRect = new RectF();
private final Matrix mShaderMatrix = new Matrix();
private final Paint mBitmapPaint = new Paint();
private final Paint mBorderPaint = new Paint();
private final Paint mFillPaint = new Paint();
private int mBorderColor = DEFAULT_BORDER_COLOR;
private int mBorderWidth = DEFAULT_BORDER_WIDTH;
private int mFillColor = DEFAULT_FILL_COLOR;
private Bitmap mBitmap;
private BitmapShader mBitmapShader;
private int mBitmapWidth;
private int mBitmapHeight;
private float mDrawableRadius;
private float mBorderRadius;
private ColorFilter mColorFilter;
private boolean mReady;
private boolean mSetupPending;
private boolean mBorderOverlay;
private boolean mDisableCircularTransformation;
public CircleImageView(Context context) {
super(context);
init();
}
public CircleImageView(Context context, AttributeSet attrs) {
this(context, attrs, 0);
}
public CircleImageView(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
TypedArray a = context.obtainStyledAttributes(attrs, R.styleable.CircleImageView, defStyle, 0);
mBorderWidth = a.getDimensionPixelSize(R.styleable.CircleImageView_civ_border_width, DEFAULT_BORDER_WIDTH);
mBorderColor = a.getColor(R.styleable.CircleImageView_civ_border_color, DEFAULT_BORDER_COLOR);
mBorderOverlay = a.getBoolean(R.styleable.CircleImageView_civ_border_overlay, DEFAULT_BORDER_OVERLAY);
mFillColor = a.getColor(R.styleable.CircleImageView_civ_fill_color, DEFAULT_FILL_COLOR);
a.recycle();
init();
}
private void init() {
super.setScaleType(SCALE_TYPE);
mReady = true;
if (mSetupPending) {
setup();
mSetupPending = false;
}
}
@Override
public ScaleType getScaleType() {
return SCALE_TYPE;
}
@Override
public void setScaleType(ScaleType scaleType) {
if (scaleType != SCALE_TYPE) {
throw new IllegalArgumentException(String.format("ScaleType %s not supported.", scaleType));
}
}
@Override
public void setAdjustViewBounds(boolean adjustViewBounds) {
if (adjustViewBounds) {
throw new IllegalArgumentException("adjustViewBounds not supported.");
}
}
@Override
protected void onDraw(Canvas canvas) {
if (mDisableCircularTransformation) {
super.onDraw(canvas);
return;
}
if (mBitmap == null) {
return;
}
if (mFillColor != Color.TRANSPARENT) {
canvas.drawCircle(mDrawableRect.centerX(), mDrawableRect.centerY(), mDrawableRadius, mFillPaint);
}
canvas.drawCircle(mDrawableRect.centerX(), mDrawableRect.centerY(), mDrawableRadius, mBitmapPaint);
if (mBorderWidth > 0) {
canvas.drawCircle(mBorderRect.centerX(), mBorderRect.centerY(), mBorderRadius, mBorderPaint);
}
}
@Override
protected void onSizeChanged(int w, int h, int oldw, int oldh) {
super.onSizeChanged(w, h, oldw, oldh);
setup();
}
@Override
public void setPadding(int left, int top, int right, int bottom) {
super.setPadding(left, top, right, bottom);
setup();
}
@Override
public void setPaddingRelative(int start, int top, int end, int bottom) {
super.setPaddingRelative(start, top, end, bottom);
setup();
}
public int getBorderColor() {
return mBorderColor;
}
public void setBorderColor(@ColorInt int borderColor) {
if (borderColor == mBorderColor) {
return;
}
mBorderColor = borderColor;
mBorderPaint.setColor(mBorderColor);
invalidate();
}
/**
* @deprecated Use {@link #setBorderColor(int)} instead
*/
@Deprecated
public void setBorderColorResource(@ColorRes int borderColorRes) {
setBorderColor(getContext().getResources().getColor(borderColorRes));
}
/**
* Return the color drawn behind the circle-shaped drawable.
*
* @return The color drawn behind the drawable
* @deprecated Fill color support is going to be removed in the future
*/
@Deprecated
public int getFillColor() {
return mFillColor;
}
/**
* Set a color to be drawn behind the circle-shaped drawable. Note that
* this has no effect if the drawable is opaque or no drawable is set.
*
* @param fillColor The color to be drawn behind the drawable
* @deprecated Fill color support is going to be removed in the future
*/
@Deprecated
public void setFillColor(@ColorInt int fillColor) {
if (fillColor == mFillColor) {
return;
}
mFillColor = fillColor;
mFillPaint.setColor(fillColor);
invalidate();
}
public int getBorderWidth() {
return mBorderWidth;
}
public void setBorderWidth(int borderWidth) {
if (borderWidth == mBorderWidth) {
return;
}
mBorderWidth = borderWidth;
setup();
}
public boolean isBorderOverlay() {
return mBorderOverlay;
}
public void setBorderOverlay(boolean borderOverlay) {
if (borderOverlay == mBorderOverlay) {
return;
}
mBorderOverlay = borderOverlay;
setup();
}
public boolean isDisableCircularTransformation() {
return mDisableCircularTransformation;
}
public void setDisableCircularTransformation(boolean disableCircularTransformation) {
if (mDisableCircularTransformation == disableCircularTransformation) {
return;
}
mDisableCircularTransformation = disableCircularTransformation;
initializeBitmap();
}
@Override
public void setImageBitmap(Bitmap bm) {
super.setImageBitmap(bm);
initializeBitmap();
}
@Override
public void setImageDrawable(Drawable drawable) {
super.setImageDrawable(drawable);
initializeBitmap();
}
@Override
public void setImageResource(@DrawableRes int resId) {
super.setImageResource(resId);
initializeBitmap();
}
@Override
public void setImageURI(Uri uri) {
super.setImageURI(uri);
initializeBitmap();
}
@Override
public ColorFilter getColorFilter() {
return mColorFilter;
}
@Override
public void setColorFilter(ColorFilter cf) {
if (cf == mColorFilter) {
return;
}
mColorFilter = cf;
applyColorFilter();
invalidate();
}
private void applyColorFilter() {
if (mBitmapPaint != null) {
mBitmapPaint.setColorFilter(mColorFilter);
}
}
private Bitmap getBitmapFromDrawable(Drawable drawable) {
if (drawable == null) {
return null;
}
if (drawable instanceof BitmapDrawable) {
return ((BitmapDrawable) drawable).getBitmap();
}
try {
Bitmap bitmap;
if (drawable instanceof ColorDrawable) {
bitmap = Bitmap.createBitmap(COLORDRAWABLE_DIMENSION, COLORDRAWABLE_DIMENSION, BITMAP_CONFIG);
} else {
bitmap = Bitmap.createBitmap(drawable.getIntrinsicWidth(), drawable.getIntrinsicHeight(), BITMAP_CONFIG);
}
Canvas canvas = new Canvas(bitmap);
drawable.setBounds(0, 0, canvas.getWidth(), canvas.getHeight());
drawable.draw(canvas);
return bitmap;
} catch (Exception e) {
e.printStackTrace();
return null;
}
}
private void initializeBitmap() {
if (mDisableCircularTransformation) {
mBitmap = null;
} else {
mBitmap = getBitmapFromDrawable(getDrawable());
}
setup();
}
private void setup() {
if (!mReady) {
mSetupPending = true;
return;
}
if (getWidth() == 0 && getHeight() == 0) {
return;
}
if (mBitmap == null) {
invalidate();
return;
}
mBitmapShader = new BitmapShader(mBitmap, Shader.TileMode.CLAMP, Shader.TileMode.CLAMP);
mBitmapPaint.setAntiAlias(true);
mBitmapPaint.setShader(mBitmapShader);
mBorderPaint.setStyle(Paint.Style.STROKE);
mBorderPaint.setAntiAlias(true);
mBorderPaint.setColor(mBorderColor);
mBorderPaint.setStrokeWidth(mBorderWidth);
mFillPaint.setStyle(Paint.Style.FILL);
mFillPaint.setAntiAlias(true);
mFillPaint.setColor(mFillColor);
mBitmapHeight = mBitmap.getHeight();
mBitmapWidth = mBitmap.getWidth();
mBorderRect.set(calculateBounds());
mBorderRadius = Math.min((mBorderRect.height() - mBorderWidth) / 2.0f, (mBorderRect.width() - mBorderWidth) / 2.0f);
mDrawableRect.set(mBorderRect);
if (!mBorderOverlay && mBorderWidth > 0) {
mDrawableRect.inset(mBorderWidth - 1.0f, mBorderWidth - 1.0f);
}
mDrawableRadius = Math.min(mDrawableRect.height() / 2.0f, mDrawableRect.width() / 2.0f);
applyColorFilter();
updateShaderMatrix();
invalidate();
}
private RectF calculateBounds() {
int availableWidth = getWidth() - getPaddingLeft() - getPaddingRight();
int availableHeight = getHeight() - getPaddingTop() - getPaddingBottom();
int sideLength = Math.min(availableWidth, availableHeight);
float left = getPaddingLeft() + (availableWidth - sideLength) / 2f;
float top = getPaddingTop() + (availableHeight - sideLength) / 2f;
return new RectF(left, top, left + sideLength, top + sideLength);
}
private void updateShaderMatrix() {
float scale;
float dx = 0;
float dy = 0;
mShaderMatrix.set(null);
if (mBitmapWidth * mDrawableRect.height() > mDrawableRect.width() * mBitmapHeight) {
scale = mDrawableRect.height() / (float) mBitmapHeight;
dx = (mDrawableRect.width() - mBitmapWidth * scale) * 0.5f;
} else {
scale = mDrawableRect.width() / (float) mBitmapWidth;
dy = (mDrawableRect.height() - mBitmapHeight * scale) * 0.5f;
}
mShaderMatrix.setScale(scale, scale);
mShaderMatrix.postTranslate((int) (dx + 0.5f) + mDrawableRect.left, (int) (dy + 0.5f) + mDrawableRect.top);
mBitmapShader.setLocalMatrix(mShaderMatrix);
}
}
此外，这些是XML的属性
<?xml version="1.0" encoding="utf-8"?>
<resources>
<declare-styleable name="CircleImageView">
<attr name="civ_border_width" format="dimension" />
<attr name="civ_border_color" format="color" />
<attr name="civ_border_overlay" format="boolean" />
<attr name="civ_fill_color" format="color" />
</declare-styleable>
</resources>
在布局文件中使用它
<YOUR_PACKAGE.CircleImageView
android:id="@+id/imageUser"
android:layout_width="120dp"
android:layout_height="120dp"
android:layout_marginTop="20dp"
/>