为 ListView 中的 TextView 设置多个不同的字体

Question

我有一个显示 TextView 列表的 ListView。我希望每个 TextView 都以适当的字体显示。作为字体 String[] 数组的一部分出现在 ListView 中的字体名称与创建字体时的拼写相同。

    ListView fontsListView = (ListView) this.view.findViewById(R.id.MenuLayout);
    final String[] fonts = new String[] {
            "Aclonica",
            "Amino-Regular",
    };
    ArrayList<String> fontsList = new ArrayList<String>();
    fontsList.addAll( Arrays.asList(fonts) );
    ArrayAdapter<String> listAdapter = new ArrayAdapter<String>(getActivity(), R.layout.fonts_simple_row, fontsList);
        final TextView[] textViewArray = new TextView[0];
        for( int i = 0; i <= fonts.length - 1; i++) {
            textViewArray[i].setTypeface(Typeface.createFromAsset(getActivity().getAssets(), "fonts/" + fonts[i] + ".ttf"));
        }
    fontsListView.setAdapter(listAdapter);

还有 XML：

<TextView xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceLarge"
android:textColor="#ffffff"
android:id="@+id/rowTextView"
android:textSize="20sp"
android:gravity="center_horizontal"
android:padding="10dp"
android:typeface="sans"
android:fontFamily="sans-serif-light" />

为什么我不能让 ListView 中的每个 TextView 都有正确的 Typface？

Answer 1

ArrayAdapter<String> listAdapter = new ArrayAdapter<String>(getApplicationContext(),R.layout.fonts_simple_row,value) {
@Override
 public View getView(int position, View convertView,ViewGroup parent) {
     View view = super.getView(position, convertView, parent);
     TextView textView = (TextView) view.findViewById(R.id.rowTextView); 
     textView.setTypeface(Typeface.createFromAsset(getActivity().getAssets(),"fonts/" + fonts[position] + ".ttf"));
     return view;
 }
 };

fontsListView.setAdapter(arrayAdapter);

Answer 2

您应该使用自定义数组适配器并在 get view 方法上设置字体。

  public class MySimpleArrayAdapter extends ArrayAdapter<String> {
      private final Context context;
      private final String[] values;

      public MySimpleArrayAdapter(Context context, String[] values) {
        super(context, R.layout.rowlayout, values);
        this.context = context;
        this.values = values;
      }

      @Override
      public View getView(int position, View convertView, ViewGroup parent) {
        LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        View rowView = inflater.inflate(R.layout.rowlayout, parent, false);
        TextView textView = (TextView) rowView.findViewById(R.id.label);

        textView.setText(values[position]);
        String s = values[position];
        if (s.equals("Arial")) {
            // set textView font to arial
        } else if (s.equals("Roboto")){
            // set textView font to roboto
        }

        return rowView;
      }
    } 

Answer 3

只创建一次字体并使用它。避免在 getview 方法中创建字体。如果您不保持可重用性，它会在您每次滚动时创建。

使用ViewHolder 模式在列表视图中获得更好的性能

下面我已经尝试给出这两件事。我也在评论中给出了解释。如果对您有帮助，请检查一下。

public class AdapterFontViewHolder extends ArrayAdapter<String> {
        private final Context context;
        private final String[] values;
        Typeface typefaceArial, typefaceRoboto;
        private Typeface[] fonts;

        public AdapterFontViewHolder(Context context, String[] values) {
            super(context, R.layout.rowlayout, values);
            this.context = context;
            this.values = values;
            // Create Typeface only once and use it.. Path you can change as per your directory
            fonts = new Typeface[]{
                    Typeface.createFromAsset(context.getAssets(), "fonts/Aclonica.ttf"),
                    Typeface.createFromAsset(context.getAssets(), "fonts/Amino-Regular.ttf"),
            };
        }

        public class ViewHolder {
            TextView textView;
        }

        @Override
        public View getView(int position, View convertView, ViewGroup parent) {
            ViewHolder vHolder;
            if (convertView == null) {
                // Create Instnce of view if its null & store object in ViewHolder (a class)
                vHolder = new ViewHolder();
                convertView = LayoutInflater.from(context).inflate(R.layout.rowlayout, parent, false);
                vHolder.textView = (TextView) convertView.findViewById(R.id.label);

                //Set ViewHolder instance in convertview in a tag as a object
                convertView.setTag(vHolder);
            } else {
                // reuse as already converview is instansiated & it holds ViewHolder instance in tag
                vHolder = (ViewHolder) convertView.getTag();
            }

            vHolder.textView.setText(values[position]);

            //Here From Fonts array take Typeface
            vHolder.textView.setTypeface(fonts[position]);
            return convertView;
        }
    }

设置适配器

ListView fontsListView = (ListView) this.view.findViewById(R.id.MenuLayout);
        AdapterFontViewHolder listAdapter = new AdapterFontViewHolder(getActivity(), R.layout.fonts_simple_row, fontsList);
        fontsListView.setAdapter(listAdapter);