Question

我正在打开Web视图中的URL。初始值为input field为空白，应用程序中为button。单击按钮后，我正在打开相机并捕获图像并返回到我的网站视图以显示图像。

问题是最初，输入字段为空白。现在，当我单击按钮以捕获图像时，我在输入字段中键入“ abc”。显示了图像，但重新加载了Web视图，并且我的输入字段再次变为空白，为什么？它应该保持他的状态。

package com.example.myapp.myapplication;

import android.Manifest;
import android.app.Activity;
import android.content.Intent;
import android.content.pm.PackageManager;
import android.graphics.Bitmap;
import android.os.Bundle;
import android.support.annotation.NonNull;
import android.support.v7.app.AppCompatActivity;
import android.util.Base64;
import android.util.Log;
import android.webkit.JavascriptInterface;
import android.webkit.WebChromeClient;
import android.webkit.WebView;
import android.widget.Toast;

import java.io.ByteArrayOutputStream;

public class MainActivity extends AppCompatActivity {
    private static final int CAMERA_REQUEST = 1888;
    private static final int MY_CAMERA_PERMISSION_CODE = 100;
    WebView webView;
    public static Bitmap photo;


    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        webView = (WebView) findViewById(R.id.webview);
         webView.loadUrl("http://100.50.100.97:32671");
       // webView.loadUrl("http://115.10.74.180:30019");
        JavaScriptInterface jsInterface = new JavaScriptInterface(this);
        webView.getSettings().setJavaScriptEnabled(true);
        webView.setWebChromeClient(new WebChromeClient());
        webView.addJavascriptInterface(jsInterface, "JSInterface");
    }

    @Override
    public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
        super.onRequestPermissionsResult(requestCode, permissions, grantResults);
        if (requestCode == MY_CAMERA_PERMISSION_CODE) {
            if (grantResults[0] == PackageManager.PERMISSION_GRANTED) {
                Toast.makeText(this, "camera permission granted", Toast.LENGTH_LONG).show();
                Intent cameraIntent = new Intent(android.provider.MediaStore.ACTION_IMAGE_CAPTURE);
                startActivityForResult(cameraIntent, CAMERA_REQUEST);
            } else {
                Toast.makeText(this, "camera permission denied", Toast.LENGTH_LONG).show();
            }
        }

    }

    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        if (requestCode == CAMERA_REQUEST && resultCode == Activity.RESULT_OK) {
             photo = (Bitmap) data.getExtras().get("data");
          //  Log.d("My map",photo,"");
            if (webView != null) {
                // webView.loadUrl("http://100.50.100.97:32671");
                webView.loadUrl("http://115.10.74.180:30019");
            }
        }
    }

    public void checkTest(){
        if (checkSelfPermission(Manifest.permission.CAMERA) != PackageManager.PERMISSION_GRANTED) {
            requestPermissions(new String[]{Manifest.permission.CAMERA}, MY_CAMERA_PERMISSION_CODE);
        } else {
            Intent cameraIntent = new Intent(android.provider.MediaStore.ACTION_IMAGE_CAPTURE);
            startActivityForResult(cameraIntent, CAMERA_REQUEST);
        }
    }
}


class JavaScriptInterface {
    private MainActivity activity;



    public JavaScriptInterface(MainActivity activity) {
        this.activity = activity;
    }

    @JavascriptInterface
    public void test() {
        this.activity.checkTest();
    }


    @JavascriptInterface
    public String bitMapToBase64()
    {
        if (MainActivity.photo != null) {
            ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();
            //add support for jpg and more.
            MainActivity.photo.compress(Bitmap.CompressFormat.PNG, 50, byteArrayOutputStream);
            byte[] byteArray = byteArrayOutputStream .toByteArray();

            String encoded = Base64.encodeToString(byteArray, Base64.DEFAULT);

            return encoded;
        }
        return "null image";
    }


}

问题就在这行

if (requestCode == CAMERA_REQUEST && resultCode == Activity.RESULT_OK) {
                 photo = (Bitmap) data.getExtras().get("data");
              //  Log.d("My map",photo,"");
                if (webView != null) {
                    // webView.loadUrl("http://100.50.100.97:32671");
                    webView.loadUrl("http://115.10.74.180:30019");
                }
            }
        }

为什么要刷新整个内容？

为什么关闭相机后，Android中的网络视图会刷新？

0 个答案: