如何在Android中将TextView的文本转换为位图？

Question

我在Android开发初学者,我试图制定一个计划,使用户可以将文本显示在TextView的(TextView中显示的是我已经从资产导入的39码条码字体的文本)按下后位图"转换为位图!" 按钮.我试过搜索谷歌,但我只是设法得到答案,如将字符串转换为位图,没有指南在哪里键入代码,所以我很混淆.我尝试使用我在谷歌搜索后尝试输入的代码来运行程序,但每次按下转换按钮时它都会崩溃.

真的希望你能帮忙!先感谢您!:d

以下是我目前的代码: -

*关于西蒙的代码编辑

在java:

public class MainActivity extends Activity 
implements OnClickListener {
    //Called when activity is first created

    TextView tv1;
    ImageView iv;
    Button b;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        TextView tv1 = (TextView) findViewById(R.id.txtV);  
        tv1.setDrawingCacheEnabled(true); 

        //To change to code 39 barCode font
        Typeface barcodefont = Typeface.createFromAsset(getAssets(),                 
                "fonts/IDAutomationHC39M_FREE.otf");         
        TextView tv = (TextView) findViewById(R.id.txtV);         
        tv.setTypeface(barcodefont);
    }

    public void onClick(View v) {

        tv1.buildDrawingCache(); 
        iv.setImageBitmap(tv1.getDrawingCache()); 
    } 

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        getMenuInflater().inflate(R.menu.activity_main, menu);
        return true;
    }
}

Logcat错误:

10-04 06:33:25.076: E/AndroidRuntime(1423): FATAL EXCEPTION: main
10-04 06:33:25.076: E/AndroidRuntime(1423): java.lang.IllegalStateException: Could not find a method ConvertText(View) in the activity class com.example.txtvbitmapconverter.MainActivity for onClick handler on view class android.widget.Button with id 'btnConvert'
10-04 06:33:25.076: E/AndroidRuntime(1423):     at android.view.View$1.onClick(View.java:3578)
10-04 06:33:25.076: E/AndroidRuntime(1423):     at android.view.View.performClick(View.java:4084)
10-04 06:33:25.076: E/AndroidRuntime(1423):     at android.view.View$PerformClick.run(View.java:16966)
10-04 06:33:25.076: E/AndroidRuntime(1423):     at android.os.Handler.handleCallback(Handler.java:615)
10-04 06:33:25.076: E/AndroidRuntime(1423):     at android.os.Handler.dispatchMessage(Handler.java:92)
10-04 06:33:25.076: E/AndroidRuntime(1423):     at android.os.Looper.loop(Looper.java:137)
10-04 06:33:25.076: E/AndroidRuntime(1423):     at android.app.ActivityThread.main(ActivityThread.java:4745)
10-04 06:33:25.076: E/AndroidRuntime(1423):     at java.lang.reflect.Method.invokeNative(Native Method)
10-04 06:33:25.076: E/AndroidRuntime(1423):     at java.lang.reflect.Method.invoke(Method.java:511)
10-04 06:33:25.076: E/AndroidRuntime(1423):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:786)
10-04 06:33:25.076: E/AndroidRuntime(1423):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
10-04 06:33:25.076: E/AndroidRuntime(1423):     at dalvik.system.NativeStart.main(Native Method)
10-04 06:33:25.076: E/AndroidRuntime(1423): Caused by: java.lang.NoSuchMethodException: ConvertText [class android.view.View]
10-04 06:33:25.076: E/AndroidRuntime(1423):     at java.lang.Class.getConstructorOrMethod(Class.java:460)
10-04 06:33:25.076: E/AndroidRuntime(1423):     at java.lang.Class.getMethod(Class.java:915)
10-04 06:33:25.076: E/AndroidRuntime(1423):     at android.view.View$1.onClick(View.java:3571)
10-04 06:33:25.076: E/AndroidRuntime(1423):     ... 11 more

Answer 1

试试这个

添加到你的onCreate()

tv1.setDrawingCacheEnabled(true);

然后在你的onClick()

tv1.buildDrawingCache();
iv.setImageBitmap(tv1.getDrawingCache());

http://developer.android.com/reference/android/view/View.html#buildDrawingCache(boolean)

http://developer.android.com/reference/android/view/View.html#getDrawingCache(boolean)

[编辑]

您现在遇到的问题是您在tv1存在之前尝试启用绘图缓存.

你应该做这个:

TextView tv1 = (TextView) findViewById(R.id.txtV); 
tv1.setDrawingCacheEnabled(true);