@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
final int widthMode = MeasureSpec.getMode(widthMeasureSpec);
final int heightMode = MeasureSpec.getMode(heightMeasureSpec);
final int widthSize = MeasureSpec.getSize(widthMeasureSpec);
final int heightSize = MeasureSpec.getSize(heightMeasureSpec);
final int w;
final int h;
if (adapter != null) {
this.rowCount = adapter.getRowCount();
this.columnCount = adapter.getColumnCount();
widths = new int[columnCount + 1];
for (int i = -1; i < columnCount; i++) {
widths[i + 1] += adapter.getWidth(i);
}
heights = new int[rowCount + 1];
for (int i = -1; i < rowCount; i++) {
heights[i + 1] += adapter.getHeight(i);
}
if (widthMode == MeasureSpec.AT_MOST) {
w = Math.min(widthSize, sumArray(widths));
} else if (widthMode == MeasureSpec.UNSPECIFIED) {
w = sumArray(widths);
} else {
w = widthSize;
int sumArray = sumArray(widths);
if (sumArray < widthSize) {
final float factor = widthSize / (float) sumArray;
for (int i = 1; i < widths.length; i++) {
widths[i] = Math.round(widths[i] * factor);
}
widths[0] = widthSize - sumArray(widths, 1, widths.length - 1);
}
}
if (heightMode == MeasureSpec.AT_MOST) {
h = Math.min(heightSize, sumArray(heights));
} else if (heightMode == MeasureSpec.UNSPECIFIED) {
h = sumArray(heights);
} else {
h = heightSize;
}
} else {
if (heightMode == MeasureSpec.AT_MOST || widthMode == MeasureSpec.UNSPECIFIED) {
w = 0;
h = 0;
} else {
w = widthSize;
h = heightSize;
}
}
if (firstRow >= rowCount || getMaxScrollY() - getActualScrollY() < 0) {
firstRow = 0;
scrollY = Integer.MAX_VALUE;
}
if (firstColumn >= columnCount || getMaxScrollX() - getActualScrollX() < 0) {
firstColumn = 0;
scrollX = Integer.MAX_VALUE;
}
setMeasuredDimension(w, h);
}
