MainActivity 签名页面
package com.sign.webview;import android.app.Activity;import android.content.Intent;import android.os.Build;import android.os.Bundle;import android.view.View;import android.webkit.ValueCallback;import android.webkit.WebView;import android.webkit.WebViewClient;public class MainActivity extends Activity {private WebView _webview;@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);_webview = findViewById(R.id.webview);_webview.getSettings().setJavaScriptEnabled(true);_webview.getSettings().setAllowUniversalAccessFromFileURLs(true);_webview.setWebViewClient(new WebViewClient());_webview.addJavascriptInterface(new Bridge(), "bridge");_webview.loadUrl("file:///android_asset/index.html");findViewById(R.id.btn_clear).setOnClickListener(new View.OnClickListener() {@Overridepublic void onClick(View v) {_webview.loadUrl("javascript:clear()");}});findViewById(R.id.btn_save).setOnClickListener(new View.OnClickListener() {@Overridepublic void onClick(View v) {if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT) {System.out.println("============ 开始保存 ============");_webview.evaluateJavascript("save()", new ValueCallback<String>() {@Overridepublic void onReceiveValue(String value) {System.out.println("============ 保存结束 ============" + Bridge.sb);Intent intent = new Intent(MainActivity.this,Main2Activity.class);intent.putExtra("url", String.valueOf(Bridge.sb));startActivity(intent);}});}}});}}
MainActivity 布局文件
<?xml version="1.0" encoding="utf-8"?><LinearLayout xmlns:android="/apk/res/android"android:layout_width="match_parent"android:layout_height="match_parent"><LinearLayoutandroid:layout_width="wrap_content"android:layout_height="match_parent"android:orientation="vertical"><Buttonandroid:id="@+id/btn_clear"android:layout_width="wrap_content"android:layout_height="wrap_content"android:text="清空" /><Buttonandroid:id="@+id/btn_save"android:layout_width="wrap_content"android:layout_height="wrap_content"android:text="保存" /></LinearLayout><WebViewandroid:id="@+id/webview"android:layout_width="match_parent"android:layout_height="match_parent"></WebView></LinearLayout>
保存后的字符串拼接转为bitmap图片显示
package com.sign.webview;import android.app.Activity;import android.graphics.Bitmap;import android.graphics.BitmapFactory;import android.os.Bundle;import android.util.Base64;import android.util.Log;import android.widget.ImageView;public class Main2Activity extends Activity {@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_main2);ImageView imageView = findViewById(R.id.image);String url = getIntent().getStringExtra("url");imageView.setImageBitmap(stringtoBitmap(Stringbehind(url,"data:image/png;base64,")));//截取data:image/png;base64}public static String Stringbehind(String content, String string) {//截取之后的字符int length = string.length();String str = content.substring(content.indexOf(string));return str.substring(length);}public Bitmap stringtoBitmap(String string) {//将字符串转换成Bitmap类型Bitmap bitmap = null;try {byte[] bitmapArray;bitmapArray = Base64.decode(string, Base64.DEFAULT);bitmap = BitmapFactory.decodeByteArray(bitmapArray, 0, bitmapArray.length);} catch (Exception e) {e.printStackTrace();Log.e("xhx", "base64转换图片异常");}return bitmap;}}
本地所需签名文件请在demo中下载
签名demo链接
