TextView在同一个ButtonClick-未完成时更改为ImageView

Question

我有一个按钮。在onClick（）中它将同时显示TextView和ImageView，结果相同。但是我遇到问题，图像没有完全加载。有谁能告诉我为什么会这样？提前致谢！

Button onClick的代码

  b.setOnClickListener(new OnClickListener() {

        @Override     
        public void onClick(View view) {

            switch(count){
            case 0 :
                    df = Typeface.createFromAsset(getAssets(),                 
                            "fonts/IDAutomationHC39M_FREE.otf"); 
                    ConvertToBitmap();
                 break;
            case 1:
                    df = Typeface.createFromAsset(getAssets(),                 
                            "fonts/code128.ttf");
                    ConvertToBitmap();
                    break;
            case 2: 
                    df = Typeface.createFromAsset(getAssets(),                 
                        "fonts/Molot.otf");
                    ConvertToBitmap();
                break;
            case 3:
                    df = Typeface.createFromAsset(getAssets(),                 
                        "fonts/Days.otf");
                    ConvertToBitmap();
                break;
            case 4:
                    df = Typeface.createFromAsset(getAssets(),                 
                        "fonts/Paranoid.otf");
                    ConvertToBitmap();
                break;

            }
        }

    });

TextView和ImageView的代码

public void ConvertToBitmap(){
        if (et.getText().toString().equals("")) {

            //Clear textView
            tv.setText("");          
            et.setText("");
            tv.buildDrawingCache();
            iv.setImageBitmap(tv.getDrawingCache());

        }
        else { 
            TextView tv1 = (TextView) findViewById(R.id.textView1);
            tv1.setTypeface(df);

            String editTextValue = et.getText().toString();            
            tv.setText(editTextValue);

            tv.buildDrawingCache();
            bmap = tv.getDrawingCache();
            iv.setImageBitmap(bmap);


        }
    }

EDITED！ Layout.xml

<?xml version="1.0" encoding="utf-8"?> 
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/gameScreen"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:layout_weight="1"

android:orientation="vertical" xmlns:app="http://schemas.android.com/tools">

<com.example.textdrawn3.Text
    android:id="@+id/textDrawn"
    android:layout_width="match_parent"
    android:layout_height="46dp"
    android:layout_weight="3.11" />

    <TextView
    android:id="@+id/textView1"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_weight="0.75"
    android:text="TextView" />

    <ImageView
        android:id="@+id/imageView1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_weight="0.75"
        android:orientation="horizontal"
        android:src="@drawable/ic_launcher" />

<LinearLayout
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_gravity="bottom"
    android:background="#0000cd"
    android:orientation="horizontal" >

    <Button
        android:id="@+id/btnText"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Text"
        android:textColor="#ffffff"
        android:textSize="25sp"
        android:typeface="serif" />

    <Button
        android:id="@+id/btnStop"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Stop"
        android:textColor="#ffffff"
        android:textSize="25sp"
        android:typeface="serif" />

    <Button
        android:id="@+id/btnOK"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="OK"
        android:textColor="#ffffff"
        android:textSize="25sp"
        android:typeface="serif" />

    <Button
        android:id="@+id/btnImage"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Image"
        android:textColor="#ffffff"
        android:textSize="25sp"
        android:typeface="serif" />

    <Spinner
        android:id="@+id/fonts_spinner"
        android:layout_width="135dp"
        android:layout_height="wrap_content"
        android:textAlignment="center"
        app:context=".TextDrawn3" />

    <EditText
        android:id="@+id/editText1"
        android:layout_width="140dp"
        android:layout_height="wrap_content"
        android:ems="10"
        android:freezesText="false"
        android:hint="text"
        android:maxLength="10"
        android:maxLines="1"
        android:textAlignment="center"
        android:textColor="#e6e6fa"
        android:textSize="25sp"
        android:typeface="serif"
        android:visibility="visible" >

        <requestFocus />
    </EditText>

</LinearLayout>