实际上我并不了解如何在相机预览中实现矩形。一切运作良好，但我不知道像这个链接放置矩形边框的方法。请有人帮帮我。感谢。
package com.example.redsignal.eventbizz;
public class CameraActivity extends AppCompatActivity {
public static final String FRAGMENT_TAG = "camera";
private static final int REQUEST_CAMERA_PERMISSIONS = 931;
private static final int REQUEST_PREVIEW_CODE = 1001;
@Bind(R.id.settings_view)
CameraSettingsView settingsView;
@Bind(R.id.flash_switch_view)
FlashSwitchView flashSwitchView;
@Bind(R.id.front_back_camera_switcher)
CameraSwitchView cameraSwitchView;
@Bind(R.id.record_button)
RecordButton recordButton;
@Bind(R.id.cameraLayout)
View cameraLayout;
Button btn_orc, btn_qr;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_camera);
ActionBar actionBar = getSupportActionBar();
actionBar.hide();
ButterKnife.bind(this);
btn_orc = (Button) findViewById(R.id.btn_orc);
btn_orc.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Intent intent = new Intent(CameraActivity.this, CameraActivity.class);
startActivity(intent);
TastyToast.makeText(CameraActivity.this, "BCR Mode", TastyToast.LENGTH_LONG, TastyToast.INFO);
finish();
}
});
btn_qr = (Button) findViewById(R.id.btn_qr);
btn_qr = (Button) findViewById(R.id.btn_qr);
btn_qr.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Intent intent = new Intent(CameraActivity.this, QRCameraActivity.class);
startActivity(intent);
TastyToast.makeText(CameraActivity.this, "QR Mode", TastyToast.LENGTH_LONG, TastyToast.INFO);
finish();
}
});
if (Build.VERSION.SDK_INT > 15) {
final String[] permissions = {
Manifest.permission.CAMERA,
Manifest.permission.RECORD_AUDIO,
Manifest.permission.WRITE_EXTERNAL_STORAGE,
Manifest.permission.READ_EXTERNAL_STORAGE};
final List<String> permissionsToRequest = new ArrayList<>();
for (String permission : permissions) {
if (ActivityCompat.checkSelfPermission(this, permission) != PackageManager.PERMISSION_GRANTED) {
permissionsToRequest.add(permission);
}
}
if (!permissionsToRequest.isEmpty()) {
ActivityCompat.requestPermissions(this, permissionsToRequest.toArray(new String[permissionsToRequest.size()]), REQUEST_CAMERA_PERMISSIONS);
} else addCamera();
} else {
addCamera();
}
}
@OnClick(R.id.flash_switch_view)
public void onFlashSwitcClicked() {
final CameraFragmentApi cameraFragment = getCameraFragment();
if (cameraFragment != null) {
cameraFragment.toggleFlashMode();
}
}
@OnClick(R.id.front_back_camera_switcher)
public void onSwitchCameraClicked() {
final CameraFragmentApi cameraFragment = getCameraFragment();
if (cameraFragment != null) {
cameraFragment.switchCameraTypeFrontBack();
}
}
@OnClick(R.id.record_button)
public void onRecordButtonClicked() {
final CameraFragmentApi cameraFragment = getCameraFragment();
if (cameraFragment != null) {
cameraFragment.takePhotoOrCaptureVideo(new CameraFragmentResultAdapter() {
@Override
public void onPhotoTaken(byte[] bytes, String filePath) {
Toast.makeText(getBaseContext(), "onPhotoTaken " + filePath, Toast.LENGTH_SHORT).show();
}
},
"/storage/self/primary",
"photo0");
}
}
@OnClick(R.id.settings_view)
public void onSettingsClicked() {
final CameraFragmentApi cameraFragment = getCameraFragment();
if (cameraFragment != null) {
cameraFragment.openSettingDialog();
}
}
@Override
public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
super.onRequestPermissionsResult(requestCode, permissions, grantResults);
if (grantResults.length != 0) {
addCamera();
}
}
@RequiresPermission(Manifest.permission.CAMERA)
public void addCamera() {
cameraLayout.setVisibility(View.GONE);
cameraLayout.setVisibility(View.VISIBLE);
final CameraFragment cameraFragment = CameraFragment.newInstance(new Configuration.Builder()
.setCamera(Configuration.CAMERA_FACE_REAR).build());
getSupportFragmentManager().beginTransaction()
.replace(R.id.content, cameraFragment, FRAGMENT_TAG)
.commitAllowingStateLoss();
if (cameraFragment != null) {
cameraFragment.setStateListener(new CameraFragmentStateAdapter() {
@Override
public void onCurrentCameraBack() {
cameraSwitchView.displayBackCamera();
}
@Override
public void onCurrentCameraFront() {
cameraSwitchView.displayFrontCamera();
}
@Override
public void onFlashAuto() {
flashSwitchView.displayFlashAuto();
}
@Override
public void onFlashOn() {
flashSwitchView.displayFlashOn();
}
@Override
public void onFlashOff() {
flashSwitchView.displayFlashOff();
}
@Override
public void shouldRotateControls(int degrees) {
ViewCompat.setRotation(cameraSwitchView, degrees);
ViewCompat.setRotation(flashSwitchView, degrees);
}
@Override
public void onRecordStatePhoto() {
recordButton.displayPhotoState();
}
});
cameraFragment.setControlsListener(new CameraFragmentControlsAdapter() {
@Override
public void lockControls() {
cameraSwitchView.setEnabled(false);
recordButton.setEnabled(false);
settingsView.setEnabled(false);
flashSwitchView.setEnabled(false);
}
@Override
public void unLockControls() {
cameraSwitchView.setEnabled(true);
recordButton.setEnabled(true);
settingsView.setEnabled(true);
flashSwitchView.setEnabled(true);
}
@Override
public void allowCameraSwitching(boolean allow) {
cameraSwitchView.setVisibility(allow ? View.VISIBLE : View.GONE);
}
@Override
public void allowRecord(boolean allow) {
recordButton.setEnabled(allow);
}
});
}
}
private CameraFragmentApi getCameraFragment() {
return (CameraFragmentApi) getSupportFragmentManager().findFragmentByTag(FRAGMENT_TAG);
}
<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent">
<FrameLayout
android:id="@+id/content"
android:layout_width="match_parent"
android:layout_height="match_parent"/>
<RelativeLayout
android:id="@+id/cameraLayout"
android:visibility="gone"
tools:visibility="visible"
android:layout_width="match_parent"
android:layout_height="match_parent"
>
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="60dp"
android:layout_alignParentEnd="true"
android:layout_alignParentRight="true"
android:layout_alignParentTop="true"
android:paddingTop="10dp">
<com.github.florent37.camerafragment.widgets.CameraSettingsView
android:id="@+id/settings_view"
android:layout_width="40dp"
android:layout_height="40dp"
android:layout_alignParentLeft="true"
android:layout_centerVertical="true"
android:layout_marginLeft="15dp"
tools:ignore="RtlHardcoded" />
<com.github.florent37.camerafragment.widgets.FlashSwitchView
android:id="@+id/flash_switch_view"
android:layout_width="40dp"
android:layout_height="40dp"
android:layout_centerInParent="true" />
<com.github.florent37.camerafragment.widgets.CameraSwitchView
android:id="@+id/front_back_camera_switcher"
android:layout_width="40dp"
android:layout_height="40dp"
android:layout_alignParentRight="true"
android:layout_centerVertical="true"
android:layout_marginRight="15dp"
tools:ignore="RtlHardcoded" />
</RelativeLayout>
<!--android:background="#82000000"-->
<RelativeLayout
android:id="@+id/record_panel"
android:layout_width="match_parent"
android:layout_height="80dp"
android:background="@android:color/transparent"
android:layout_alignParentBottom="true"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true">
<com.github.florent37.camerafragment.widgets.RecordButton
android:id="@+id/record_button"
android:layout_width="60dp"
android:layout_height="60dp"
android:layout_centerInParent="true"
android:layout_marginLeft="50dp"
android:layout_marginRight="50dp" />
<Button
android:id="@+id/btn_qr"
android:layout_width="30dp"
android:layout_height="30dp"
android:layout_marginTop="30dp"
android:layout_toLeftOf="@+id/btn_orc"
android:layout_toStartOf="@+id/btn_orc"
android:background="@drawable/qr_scan" />
<Button
android:id="@+id/btn_orc"
android:layout_width="30dp"
android:layout_height="30dp"
android:layout_alignParentEnd="true"
android:layout_alignParentRight="true"
android:layout_marginLeft="7dp"
android:layout_marginRight="5dp"
android:layout_alignTop="@+id/btn_qr"
android:background="@drawable/bcr_scan"
tools:ignore="RtlHardcoded" />
</RelativeLayout>
</RelativeLayout>
</FrameLayout>
答案 0 :(得分：1)
为了实现此目的，您可以将相机预览放入glm::vec4 CubeCoordinates[8]{
glm::vec4(-1.0f, -1.0f, 1.0f, 1.0f),
glm::vec4(-1.0f, 1.0f, 1.0f, 1.0f),
glm::vec4(1.0f, 1.0f, 1.0f, 1.0f),
glm::vec4(1.0f, -1.0f, 1.0f, 1.0f),
glm::vec4(-1.0f, -1.0f, -1.0f, 1.0f),
glm::vec4(-1.0f, 1.0f, -1.0f, 1.0f),
glm::vec4(1.0f, 1.0f, -1.0f, 1.0f),
glm::vec4(1.0f, -1.0f, -1.0f, 1.0f) };
glm::mat4 InvertedViewProjectionMatrix = glm::inverse(refCamera.GetViewProjectionMatrix());
for (uint32_t i = 0; i < 8; ++i)
{
CameraEdgesWorldSpace[i] = InvertedViewProjectionMatrix * CubeCoordinates[i];
}
，并将透明的FrameLayout放置在相机预览上方。
首先我们要创建矩形：
View
然后您可以将此视图放在预览上：
<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
android:shape="rectangle">
<stroke
android:width="1dp"
android:color="@color/white"
android:dashGap="8dp"
android:dashWidth="8dp" />
<corners android:radius="8dp" />
修改
看了你的布局后，只需放置htis视图即可解决任务：
<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent">
<!-- this is your preview - whatever it looks like -->
<View
android:layout_width="match_parent"
android:layout_height="match_parent" />
<!-- overlay - customize padding and stuff -->
<View
android:layout_width="match_parent"
android:layout_height="match_parent"
padding="32dp"
android:background="@drawable/your_shape" />
</FrameLayout>
作为ID为 <View
padding="32dp"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_above="@id/record_panel"
android:layout_alignParentTop="true"
android:background="@drawable/your_shape" />
答案 1 :(得分：0)
要在相机预览中绘制任何类型的视图，请 覆盖意味着绘制任何形状的画布，例如为电话制作具有特定颜色的矩形画布，该覆盖将覆盖整个屏幕。
现在，通过更改画布的Alpha值，使其变得半透明。
现在绘制另一个您需要的形状的画布，例如圆形和矩形，并使其透明。
代码如下：
public class DrawOnTop extends View {
int screenCenterX = 0;
int screenCenterY = 0;
int radius = 50;
public DrawOnTop(Context context, int screenCenterX, int screenCenterY, int radius) {
super(context);
this.screenCenterX = screenCenterX;
this.screenCenterY = screenCenterY;
this.radius = radius;
}
@Override
protected void onDraw(Canvas canvas) {
Paint paint = new Paint(Paint.ANTI_ALIAS_FLAG);
paint.setColor(getResources().getColor(R.color.white));
paint.setAlpha(130);
paint.setStyle(Paint.Style.FILL);
canvas.drawPaint(paint);
paint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.CLEAR));
canvas.drawCircle(screenCenterX, screenCenterY, radius, paint);
super.onDraw(canvas);
}
}