android - 相机应用程序在 android ffmpeg 应用程序上失败

Question

我正在尝试在 android 上运行一个简单的录像机应用程序。代码如下:

package com.example.camera

//import android.R
import android.content.DialogInterface
import android.content.pm.PackageManager
import android.os.Build
import android.os.Bundle
import android.widget.Toast
import androidx.appcompat.app.AlertDialog
import androidx.appcompat.app.AppCompatActivity
import androidx.core.app.ActivityCompat
import androidx.core.content.ContextCompat
import com.arthenica.mobileffmpeg.FFmpeg


const val EXTRA_MESSAGE = "com.example.myfirstapp.MESSAGE"

class MainActivity : AppCompatActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)
        if (checkPermission()) {
            //main logic or main code
           FFmpeg.execute("-f android_camera -i 0:0 -r 30 -pixel_format bgr0 -t 00:00:05 /sdcard/test.mp4")

            // . write your main code to execute, It will execute if the permission is already given.
        } else {
            requestPermission()
        }
    }

    private fun checkPermission(): Boolean {
        return if (ContextCompat.checkSelfPermission(this, android.Manifest.permission.CAMERA)
            != PackageManager.PERMISSION_GRANTED
        ) {
            // Permission is not granted
            false
        } else true
    }

    private fun requestPermission() {
        ActivityCompat.requestPermissions(
            this, arrayOf(android.Manifest.permission.CAMERA),
            PERMISSION_REQUEST_CODE
        )
    }

    override fun onRequestPermissionsResult(
        requestCode: Int,
        permissions: Array<String>,
        grantResults: IntArray
    ) {
        when (requestCode) {
            PERMISSION_REQUEST_CODE -> if (grantResults.size > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED
            ) {
                Toast.makeText(applicationContext, "Permission Granted", Toast.LENGTH_SHORT)
                    .show()

                // main logic
            } else {
                Toast.makeText(applicationContext, "Permission Denied", Toast.LENGTH_SHORT)
                    .show()
                if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
                    if (ContextCompat.checkSelfPermission(this, android.Manifest.permission.CAMERA)
                        != PackageManager.PERMISSION_GRANTED
                    ) {
                        showMessageOKCancel("You need to allow access permissions",
                            DialogInterface.OnClickListener { dialog, which ->
                                if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
                                    requestPermission()
                                }
                            })
                    }
                }
            }
        }
    }

    private fun showMessageOKCancel(
        message: String,
        okListener: DialogInterface.OnClickListener
    ) {
        AlertDialog.Builder(this@MainActivity)
            .setMessage(message)
            .setPositiveButton("OK", okListener)
            .setNegativeButton("Cancel", null)
            .create()
            .show()
    }

    companion object {
        private const val PERMISSION_REQUEST_CODE = 200
    }
}

调用录像机的主要命令在这里:

           FFmpeg.execute("-f android_camera -i 0:0 -r 30 -pixel_format bgr0 -t 00:00:05 /sdcard/test.mp4")

该应用程序在我的 android 10 Motorola G Power 上打开。我点击“允许”以允许权限。然后应用程序崩溃，我不断收到此错误:

2021-03-22 13:42:51.534 31138-31138/com.example.camera E/AndroidRuntime: FATAL EXCEPTION: main
    Process: com.example.camera, PID: 31138
    java.lang.IllegalStateException: Could not find method sendMessage(View) in a parent or ancestor Context for android:onClick attribute defined on view class com.google.android.material.button.MaterialButton with id 'button2'
        at androidx.appcompat.app.AppCompatViewInflater$DeclaredOnClickListener.resolveMethod(AppCompatViewInflater.java:436)
        at androidx.appcompat.app.AppCompatViewInflater$DeclaredOnClickListener.onClick(AppCompatViewInflater.java:393)
        at android.view.View.performClick(View.java:7161)
        at com.google.android.material.button.MaterialButton.performClick(MaterialButton.java:967)
        at android.view.View.performClickInternal(View.java:7133)
        at android.view.View.access$3500(View.java:804)
        at android.view.View$PerformClick.run(View.java:27416)
        at android.os.Handler.handleCallback(Handler.java:883)
        at android.os.Handler.dispatchMessage(Handler.java:100)
        at android.os.Looper.loop(Looper.java:241)
        at android.app.ActivityThread.main(ActivityThread.java:7617)
        at java.lang.reflect.Method.invoke(Native Method)
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:492)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:941)
2021-03-22 13:42:51.546 31138-31138/com.example.camera I/Process: Sending signal. PID: 31138 SIG: 9

我究竟做错了什么？请指教。
编辑
布局xml

<?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">

    <EditText
        android:id="@+id/editText"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginStart="16dp"
        android:layout_marginLeft="16dp"
        android:layout_marginEnd="16dp"
        android:layout_marginRight="16dp"
        android:ems="10"
        android:inputType="textPersonName"
        android:text="@string/edit_message"
        app:layout_constraintBaseline_toBaselineOf="@+id/button2"
        app:layout_constraintEnd_toStartOf="@+id/button2"
        app:layout_constraintHorizontal_bias="0.5"
        app:layout_constraintStart_toStartOf="parent" />

    <Button
        android:id="@+id/button2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginEnd="16dp"
        android:layout_marginRight="16dp"
        android:onClick="sendMessage"
        android:text="@string/button_send"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.5"
        app:layout_constraintStart_toEndOf="@+id/editText"
        tools:layout_editor_absoluteY="16dp" />
</androidx.constraintlayout.widget.ConstraintLayout>

Answer 1

由于您没有发布布局 xml，我假设您在 xml 中为按钮注册了单击方法并调用了方法 sendMessage .
你实际上并没有在你的 Activity 中创建方法
在您的按钮中

<Button
    android:id="@+id/button2"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_marginEnd="16dp"
    android:layout_marginRight="16dp"
    android:onClick="sendMessage"
    android:text="@string/button_send"
    app:layout_constraintEnd_toEndOf="parent"
    app:layout_constraintHorizontal_bias="0.5"
    app:layout_constraintStart_toEndOf="@+id/editText"
    tools:layout_editor_absoluteY="16dp" />

你有属性 android:onClick="sendMessage"所以现在你需要为你的 Activity 添加一个方法。

fun sendMessage(view:View){

}